SE190862C1 - - Google Patents

Description

Inventor: A Miihlbach Priority requested from 31 January 1962 (Federal Republic of Germany) The present invention relates to improvements in punching machines for punching knives () and in particular to improvements in such machines, which are driven by hydraulic or pneumatic motors.

The invention is described as an embodiment of a punching machine with a fixed stand for the workpiece and a movable punching table cooperating therewith as a movable stable member. However, the invention may not be considered limited in other respects than what appears from the appended patent claims.

During operation of punching machines, it is often necessary for the machine forwarder to install the punching member, usually called the punching table, Upper rest layer, so that the punching table in this resting position, ie its height layer before the workpiece begins, goes free From the punch knives a sufficient but not too large piece when it is swung Over these, which rest on the workpiece. Usually this distance is a few mm. When a set of punching knives is exchanged for another set with a different height or the thickness of the workpiece of another, Or an appropriate installation of the resting layer necessary or Onskyard. For this purpose, it is common for Morse hydraulic punching machines with means for changing the coupling between the drive means and the punching table, e.g. by arranging a stepped spindle, which can be turned by means of a knob for lifting or lowering the punching table. Since the punching table and its standing pillars are relatively heavy, a considerable force is required on the Iranian forwarder, especially when lifting the punching table. Drive means for maneuvering the stepped coupling should be tried, but these require a large number of extra parts without sacrificing accuracy in height installation.

Dupl. at 28 b: 11/01 Other known means for determining the rest joint by means of electro-hydraulic control means have relatively little accuracy and those which are based on the confinement of pressure fluid in the drive cylinder, when the rest layer has been reached, have the disadvantage that the punch table slowly sinks due to fluid losses. the machine forwarder often installs the rest layer higher than what is otherwise undesirable.

Accordingly, a principal object of the foregoing invention is to provide simple, robust, economical and reliable means for instillably providing an accurate and stable resting position of the punch table. To this end, and in accordance with a main feature of the present invention, there is provided a hydraulic punching machine for punching knives, comprising a movable punching means driven by a pressure fluid motor provided with means for supplying pressure fluid to a distribution and utilization system, comprising the aforementioned pressure fluid and valve fluid. , which is mechanically connected to the movable punching means for regulating the discharge of the pressure fluid in the above-mentioned system, the valve being actuated to discharge pressure fluid to a sump and relieve fluid pressure in the drive cylinder when the punching table has reached its rest position.

A further object of the invention is to achieve simplicity and accuracy in such a device, by incorporating said valve in the pressure fluid motor.

Another intention is to provide means for convenient installation of the valve for the change of the resting layer. The invention also relates to providing power-driven means for facilitating the installation of the valve for the installation of the resting layer. 2— - For this purpose and in accordance with additional features, one of two cooperating valve elements in a movable motor element, while means are provided for the installation of the other valve element by manual vaguity or by means of fluid pressure obtained from the pressure fluid cold supplying it hydraulic motor, Sven if it Sr implied, that a separate pressure fluid cold can be used if sa. onskas.

A further object of the invention is to provide in a punching machine according to the invention improved mechanical and electrical control systems, which comprise power stalls and valve elements and which are enabled by and on an advantageous salt to co-operate with the means which none of the above-mentioned main canteens.

The invention will be described in detail in the following with reference to the accompanying drawings, in which Fig. 1 is a side view of a device according to the present invention, Fig. 2 is a partial section of the device according to Fig. 1 and shows the hydraulic motor and electric and hydraulic regulating means according to an embodiment of the invention, Fig. 3 is a partial section of a valve shown in Fig. 2, the valve slide occupying another layer, Fig. 4 is a figure corresponding to Fig. 2, showing the hydraulic motor and hydraulic control means according to a second embodiment of the invention, Fig. 5 is a view. Fig. 2 is a plan view showing the hydraulic motor and electrical and hydraulic control means according to a third embodiment of the invention and Fig. 6 is a partial section of a valve device in Fig. 5, the parts of the valve occupying the second layers.

According to Figs. 1 and 2, the punching machine shown comprises a foundation 1, which on the edge is provided with a support S for the workpiece and a punching table 1, fixed to the upper end of a vertical pillar 2 and pivotable in the horizontal plane. During operation, a workpiece W of sheet material is placed on the stand of the workpiece and a punching knife D, which can be moved around as desired on the workpiece, is pressed through the sheet material by means of the punch table to cut out parts.

In the lower part of the foundation F of the machine there is a hydraulic drive device 3 for maneuvering the punch table 1. The hydraulic drive device 3 comprises a cylinder 4 and a piston 5, which Sr is provided with an axial extension 6, which passes through one end of the cylinder and by means of screws 7 Tighten the lower ankle of the pillar 2. The piston 5, the column 2 and the punching table 1 form the movable working elements of the punching machine. The upper and lower chambers of the cylinder 4 on each side of the piston are through pipelines 8 resp. 9 connected to an electromagnetic valve 10. A pipeline 11, which extends from a sump for pressure fluid, transports fluid to a pump 12 and from below under pressure to a port 12 'in the valve body, the valve as described hereinafter more in detail It is intended to direct pressure fluid through the pipe 8 into the upper chamber for the working stroke of the punch table 1 or through the pipe 9 to the lower chamber for its return stroke.

The lower part Sr of the cylinder 4 is closed by means of a lid 13, which is sealed against water lacquering by means of an O-ring 14. The lid is filled into layers by means of a number of washers 15, which engage in a groove in the inner cradle of the cylinder 4, which washers are fixed to the lid 13 by means of screw 'was 16.

The lid 13 is provided with an axial extension in the form of a sleeve 17, provided with internal passages 18. In the extension 6 of the piston an axial passage 19 is glued, which freely receives the sleeve 17 of the lid 13, which arrangement enables a space-saving construction which facilitates the arrangement of bearings for the pillar 2. The diameter of the axial passage 19 has at the outer spirit of the extension 6 of the piston a rapid transition to a relatively narrow passage 20 and forms at the transition a shoulder with a surface 30, which forms a valve set inside the main part of the axial passage. A transverse bore 21 connects the passage 20 to the pressure fluid sump. A member 22 is connected to the passages of the sleeve 17, which member at 24 is connected by means of a pin Sr to a control rod 23, which extends upwards through the axial passage, the pillar 2 and the punching table 1. In the embodiment shown, the adjusting rod 23 carries a steering wheel. 25, by means of which the member 22 can be installed vertically by rotation thereof. By means of additional connecting means, e.g. a pair of bevel gears, if desired, means for rotating the control rod can be arranged at the punch table & Lure part. A compression spring 26 on the control rod 23 carried a valve element, comprising a sleeve 27, in a position determined by a ring stop 28 fixed to the control rod 23.

As shown in Fig. 2, an opening 29 formed between the upper surface of the sleeve 27 and the surface 30. The size of this opening is determined by the weight of the movable punch and the flow rate of the pressure fluid flowing through the opening 29. Assuming constant weight and flow rate determines the pH so set the sleeve 27 to make the press table 1 rest layer in height. The sleeve 27 together with the piston 5 formed with the axial passage and the valve set thus forms an installable control valve, which is generally denoted by 31 and serves to hydraulically determine the resting position of the press table 1. If the punching table 1 falls under its permanent resting layer, the sleeve 27 according to this embodiment comes into abutment against the surface, interrupts the discharge of pressure fluid and provides lifting of the punching table. If desired, the closing element in the stable for a sleeve can have the shape of a ball, which only abuts against the edge of the part 20.

As can be seen from Figures 2 and 3, the electromagnet 10 comprises a housing 35 formed with a central chamber 46 and an annular groove 45 above the port 12 '. A valve slide 36 is supported in the housing 35 by a spring 37 which rests against a fixed ring 38. The valve slide 36 has one. longitudinal bore 39 and a transverse bore 40 for the flow of the pressure fluid to the sump. Above the valve slide 36 there is a pressure member 41, which abuts against the armature 42 of a. electromagnet 43. The electromagnet 43 is fixed to the pump 12 and the valve housing 35 by means of screws 44.

The punching work is started on the edge of the sail by electromagnet 43 being energized, e.g. with a hand lever H (fig. 1), which is arranged at the spirit of the punching table 1 and also serves to pivot the punching table about the axis of the supporting column 2. Maneuvering the handle has an effect. of a microcomputer (not shown), which on the edge of the salt wears the circuit for excitation of the electromagnet 43. Thereby the armature 42 over the pressure member 41 presses the valve slide 36 slightly against the force of the spring 37 to the E-get shown in Fig. 3, so that pressure fluid from the pump 12 flows through the port 12 ', a chamber 46 and the pipeline 8 into the chamber of the cylinder 4, which is coated (degree & piston 5).

Consequently, the moving parts are shifted, ie. the punch table 1, the pillar 2 and the piston of the punching machine down to perform a work stroke. During this movement, the opening 29 is closed due to the abutment of the sleeve 27 against the surface 30. During the punching stroke, the sleeve 27 is displaced downwards against the force of the compression spring 26 by the surface 30, while the adjusting rod 23 together with the abutment element 28 do not change. The pressure fluid in the cylinder 4 below the piston 5 flows through the pipeline g into an internal space 47 of the valve slide 36 and thence through the bores 40 and 39 to the pressure fluid sump.

The reversal of the punch table 1 after the working stroke can be started electrically either by means of a micromostable or on the edge set by the contact of the used punch knife with an electrically conductive base for the workpiece, and has no influence on the control valve file 31 to determine the punch table 1. The operation of the control valve 31 during the return of the punch table 1 to the rest position after the working stroke will be described in the following.

When the electromagnet 43 becomes energized, after the work stroke is completed, the yentil slide 36 is returned to its original stroke during the yanking of the spring 37, so that reversal of the direction of movement of the punch table is effected by hydraulic means. Pressure fluid flows from the port 12 'through the chamber 46 into the pipeline 9 and from there into the lower chamber of the cylinder 4. The opening 29 is closed by the abutment of the sleeve 27 against the surface 30, so that no pressure fluid can flow out through the passage 20. Since the piston 5 is designed as a differential piston with upper and lower surfaces 105 and 205 of different sizes, the piston and punch table 1 are moved upwards under the pressure exerted by pressure fluid against the larger surface 205 of the piston 5, the pressure fluid enclosed in the upper chamber of the cylinder 4 flowing through the pipeline 8 into the chamber 46 and thence through pipe 9 to the lower chamber. During the entire return movement of the press table 1, the mouth of the passage 20 remains closed by the sleeve 27 and is only exposed when the sleeve 27 meets the fixed abutment member 28, which is supported by the control rod 23. The pressure fluid supplied by the pump thus lifts the punch table 1, column 2 and piston Until the opening 26 is large enough to allow the pressure fluid to flow through the passage 20 and the bore 21 to the sump at discharge rate. This adjustment takes place completely automatically, the punching table 1 remaining in its rest position. As smart as the opening 29 and thereby the flow diameter is reduced or enlarged by the external inverting of the sleeve 27, the punch table 1 immediately follows this change and is moved upwards or not until the opening 29 reaches a normal flow diameter.

A further significant advantage obtained by supporting the punch table 1 at rest by means of continuously circulating pressure fluids is that the upward movement of the punch table 1 is not stopped by fixed stops or by a sudden interruption of the supply of pressure fluid, which could lead to rapid shocks and vibrations inside the machine body. Instead, the punch table is moved very evenly to its final layer by the uninterrupted flow of pressure fluid into and finally through the cylinder despite the high speed of the return motion.

In the mechanism shown in Fig. 2, the reversal is effected electrically by means of a percussion switch 57, which on the edge was adjustable so that the second time of the workpiece interruption, so that varying penetration depths in the steel of the workpiece can be obtained for complete cutting of the workpiece. The simple arrangement of the spruce striker 57 on a sea arm and a long and the space-saving construction inside the supporting pillar 2, from which a control rod extends to the front part of the punch table 1, is of great importance in the present embodiment. An angle lever 50 with a fixed pivot shaft 51, mounted inside the bearing pillar - - 2. Below the angle lever 50 is a link pivotally suspended at 53. The angle lever 50 and the Milken 52 are by means of pivot pins 54 and 55, which have the same mutual distance as the pivot shafts 51 and connected to a triangular member 56. At the lower part of the triangular member 56 the spruce current switch is fixed by means of screws 58. An installation rod 59 has a gang-ad Slide 59 ', which engages with internal passages arranged in the pillar 2. Installation rod 59 second spirit carried an installation knob 60. A short arm 50 'of the angle lever arm 50 abuts against the aisle spirit of the installation rod 59 and Mlles in this layer by means of a tension spring 61. By rotating the installation rod the parallel suspension of the angle lever arm 50 and the Milken 52 acts to lower the check switch 57. or lifted but maintained in a horizontal layer. The control rod 23 for changing the position of the punch table 1 in relation to the position of the workpiece remains at rest during the movement of the punch table 1 and this is also the case with a ring 62, arranged on the control rod 23. After the machine is started by the electromagnet 43, the pillar 2 and the control switch are moved down. , until a button 63 on the check switch 57 comes into contact with the ring 62, so that the switch 57 is operated to turn the electromagnet 43 on. The valve slide 36 is then returned to its (upper) starting position, whereby the working stroke as stated above ceases. The return movement of the punch table 1 begins at the same time and continues until its sleeve: 27 comes into abutment against the stop 28 and is retained by it, and until the opening 29 for the pressure fluid flow which carried the punch table 1 returned to its normal size.

At each change of the punching table 1 'age in height by means of the knob 25, e.g. with the intention of using punching knives of a different height, the punch X, which is once instantaneous by means of the installation knob 60, remains unchanged over the entire area for the installation of the control rod, since the percussion switch is connected to the punching parts and participates in this installation.

If it is difficult to effect the reversal of the blow by contact between the punching knife and the support of the workpiece in accordance with what is stated in the above-mentioned patent, the spruce current switch 57 and the distance X can be increased by the installation knob beyond the maximum working stroke, so that no engagement between ring 62 is possible during the work team. The special advantages of the present invention consist in that the punching machine can be adjusted without responses from reversal of the direction of movement of the punching table 1 according to the above contacted to the set with impact control, in which the reversal is achieved by means of punching current switches with the intention of making the punching machine workable.

The embodiment of the punching machine shown in Fig. 4 utilizes an additional control device for the rest of the punching table resting layer in combination with the above contact set for reversing the working stroke, yid which the punching operation is terminated by the punching knife contact with an electrically conductive star for the workpiece. The installation of the punch table 1 is effected by the genor using the pressure fluid for the hydraulic drive motor 3 '. The sleeve 17 'of the lid 13' has a smooth cylindrical bore 65 in the place of the threaded bore 18 according to Fig. 2. A piston 66 is coated in the bore 65 and fitted against water varnishing by means of 0-rings 67. The adjusting rod 68 is shorter than the adjusting rod 23 according to Fig. 2 and carried in its upper spirit a closing sleeve 27 'formed with a. guide ring flange 70. An annular member 28 'serves as abutment and limitation for the movement of the closure sleeve 27' on the adjusting rod 68. A spring 26 'holds the sleeve 27' in its 8th layer while the flange 70 slides in an axial passage 19 'of the piston extension 6 and thus controls the upper dude of the control rod 68. The flange 70 is provided with several circumferentially distributed passages 71 to enable pressure fluid flow past it. All other means of the control valve in accordance with the invention, e.g. a surface 30 ', a passage 20' and a transverse bore 21 ', have the same function with respect to pressure fluid discharge as previously described in connection with the embodiment according to Figs. 2 and 3 and the same grille for the hydraulic drive motor 3'. The installation of the piston 66 in height and thus the change of the age of the punch table 1 in relation to the workpiece stand is effected by an externally coated control valve 72. This control valve 72 has a longitudinal bore 81, into which two. gaited spindles 73 and 74 extend at right angles, the tips of the spindles being shaped like cones 73 'and 74'. The bore 81 is connected to the pressure fluid in the lower chamber 80 of the cylinder 4 'by means of a pipe 78 and to the cylinder space 82 below the piston 66 by a pipe 79. Each of the rotating spindles 73 and 74 carried a knob 76 and 77. A pipe 83 stretches Iran drilled 81 to the pressure fluid sump. The pipelines 78 and 83 are in the position shown in Fig. 4 while the machine is in the rest position (and when the work is being performed) are usually closed by the cones 73 'and 74', so that the piston 66 remains at rest, since the pressure fluid below the piston 66 is enclosed in the chamber 82 as it cannot flow past the cones 73 'and 74', because the fluid above the piston 66 in a space 85 is under pressure by connection to the chamber 80. But if the cone 73 'of the aisle spindle is moved away from the inlet of the pipe 78 by turning the air knob 76, fluid is introduced under Mgt pressure & in the bore 81 from the pipe 78 and therefrom to the pipe 79 and from the denim to the cylinder space 82 below the piston 66. if the pressure of the pressure fluid above and below the piston 66 is equal, the lower surface 66 'of the piston 66 is larger than its upper surface 66 "and thus a greater force is exerted on the surface 66' than on the surface 66", so that the piston 66 is displaced upwards until the conduit 78 returns completely to is closed by tightening the threaded spindle 73.

If in the stable the spindle 74 is rotated to open the pipe 8 to the sump, the coal 66 is moved downwards as long as the pipe 83 remains open.

If it is necessary to use another means of the pressure fluid inside the machine to maneuver the piston 66, the pipeline 78 is disconnected from the cylinder space 80 and connected on the edge of salt to an additional pressure fluid system.

In the embodiment of Figs. 5 and 6, the solenoid valve 10 with the valve slide 36 and the pipeline 9 of Figs. 2, 3 and 1 have been omitted, but the control valve 31 of Fig. 4 was used in connection with the pressure fluid for the hydraulic drive motor to effect changes in the resting layer of the punch table 1 in the manner described above. This change is effected by means of the means used in the embodiment according to Fig. 4.

The valve device for reversing the movement of the punch table 1 is in the embodiment according to Figs. 5 and 6 formed as a sleeve 90 and is arranged concentrically in an extension 6 "to the" piston 5 "of the hydraulic drive motor 3. Arranged grooves 91 and 91 'are arranged in the sleeve. 90 at equal distances from its owe and lower spirits. Each of the grooves 91 and 91 'communicates with the interior of the sleeve 90 through a number of radially extending bores 92 and 92'. In its upper layer the sleeve is held in abutment against a surface 30 "of the 18 extension 6" by means of a compression spring 93, inserted between the bottom surface 94 of the sleeve 90 and an annular member 95. The extension 6 "of the piston is alien provided with a transverse boning 96, connected to bores 97, which open into an annular channel 98. Another annular channel 99 of the piston extension 6 "is connected to the sump through a longitudinal bore 100 and a transverse bore 101. A supply line 102 is connected to an upper chamber 103 of the cylinder. n 4 ".

The layer for the sleeve 90, a piston 106, the drive coil 205 and the sleeve 27 ", shown in Fig. 5, corresponds to the resting layer according to Fig. 2. The movable parts, the punch table 1 and its supporting pillars 2 are supported by the pressure fluid flowing through the opening 29 ".

The flow of the pressure fluid when the punch is at rest is as follows: the pressure fluid, which is fed by means of a pump, Wm not shown in Fig. 5, flows through the supply line 102 into the cylinder space 103 and through bores 96 and 97 into the annular channel 98. From there the pressure fluid flows through the groove 91 'and the bores 92' into the inner space 104 of the sleeve 90 to support the movable parts 1 and 2, past the sleeve 27 'and through bores 100 and 101 back to the sump. At the same time, pressure fluid is introduced to a lower chamber 108 below the driving piston 5 "and to a space 107 above the piston 106, which space communicates with the space 104.

An electromagnet 109 for actuating the sleeve 90 and thus for initiating the working operation is fixedly arranged at the upper part of the bar column 2 "and at 111 screwed to a lid 110 thereto. The armature 112 of the electromagnet 109 acts on a rod 113 and a pin 114, which in in turn affects the sleeve 90. The stem 113 and the pin 114 are held in their upper layers according to Fig. by means of a spring 115. For initiating the working operation, a handle H (Fig. 1) is actuated at the front part of the punch table 1 to operate a power stall, thereby causing the electromagnet 109 to become current-carrying.Also, the armature 112 is caused to displace the sleeve 90 against the action of the springs 1 and 93 to the bearing shown in Fig. 6. The annular recess 91 'is thereby moved out of connection with the channel 98, so that pressure fluid in the chamber 103 can displace the working piston 5 "downwards together with the supporting pillar 2" and the punching table 1. Due to the downward movement of the sleeve 90 the groove 91 is simultaneously caused to communicate with the annular channel 99 so that pressure fluid coated below the drive piston 5 "can flow through the radial bores 92 and bores 100 and 101 to the sump. The opening 29 "is then closed by the sleeve 27", which has come into abutment against the surface 30 ". The punch table 1 continues to move neatly to perform the work stroke and is reversed at the moment in which the sleeve 90 returns to its original position, and connects the channel 99 to the sump and opens the channel between the upper and lower chambers of the 4 "cylinder. The punching table 1 then moves upwards until the opening 29 ", through which pressure fluid can be discharged, has been restored.

The electromagnet 109 is de-energized and thus the return of the sleeve 90 according to the present embodiment is achieved by contact between the punching knife and an electrically conductive part of the workpiece. However, the reinforcement of the sleeve 90 to its original bearing can also be achieved by mechanical or electrical means. 6- -

Claims (12)

Patent claim: Hydraulic punching machine for punching or perforating sheet or strip-shaped material, in particular charger, textile or the like, in which moving parts are assigned a return motion in relation to normal stationary parts by means of installable machine parts under electric or electronic control, at least an extra , preferably inside the hydraulic drive means (3, 3 ', 3 ") arranged control valve (31, 31', 31") for the movable part or parts (1, 2) of the machine comprises an optionally installable valve element (27, 27 ', 27). ") for the installation or limitation of the working part of the movable part or parts (1, 2), after their active movement to a certain age, and that a free opening (29, 29 ', 29"). is intended to be formed between the above-mentioned valve element and one of its valve sets (30, 30 ', 30 "), through which the hydraulic pressure fluid of the drive means flows during the rest state of the machine. Punching machine according to claim 1, characterized in that the valve set (30, 30 ', 30 ") of the valve element is arranged on the hydraulically active parts of the hydraulic drive device (5, 6, 102, 6', 205, 6"). Punching machine according to claims 1 and 2, characterized in that the operative part of the hydraulic drive device consists of a piston (5, 105, 205), which on one side is provided with a piston rod (6, 6 ', 6 " ) in the form of an axial extension of the piston, a passage which is open in both spirits but has different diameters along its axial length, being arranged so that an abutment surface (30, 30 ', 30 "), in the interior of The axial passage of the piston and piston rod forms the sate of the control valve. Punching machine according to claims 1 to 3, characterized in that a control rod (23, 68, 68 ') extends into the axial passage, one end of this control pin being installably received in an axial recess of a closing element (13, 13). ', 13 "). Punching machine according to any one of claims 1-4, characterized in that the axial recess of the above-mentioned closing element (13) has an internal thread (18), in which a member (22), which is fixedly connected to one of the adjusting rods (23) is such that the control rod (23) and the installable valve element, which is formed by a control sleeve (27), are displaceable in the longitudinal direction in the axial passage of the piston and the piston rod by means of a mechanical drive device (25). Punching machine according to patent claims 1-4, characterized in that the axial depression of the closing element (13, 13 ") for the cylinder (4 ', 4") has the shape of a cylindrical bore (85, 107), which movably controls one. piston (66, 106) on said one end of the control rod (68, 68 "), which piston is intended to effect installation movement of the control rod with its control sleeve (27 ', 27") under the action of pressure fluid or other means. Punching machine according to any one of claims 1-6, characterized in that the adjusting sleeve (27, 27 ', 27 ") is axially displaceable on the adjusting rod by means of a return spring (26, 26', 26"), arranged between an element (22) or piston (66., 106). of the control rod and the sleeve (27, 27 ', 27 "), so that the abutment of the sleeve in relation to the valve seat (30, 30', 30") is limited by a stop (28, 28 ', 28 ") on the control rod. Punching machine according to any one of claims 1-7, characterized in that said closing element (13, 13 ', 13 ") for the cylinder (4, 4', 4") is ground against the cylinder as a lid, which has a cylindrical longitudinal flap ( 17, 17 ', 17 "), which extends freely into the axial passage of the piston (19, 19', 19"). 4. Punching machine according to any one of claims 1-8, characterized in that the piston (5, of the hydraulic drive device) 105, 205) is formed as a differential piston, the piston rod (6, 6 ', 6 ") extending from the smaller piston surface (5") receiving in one end the valve seat (30, 30', -30 ") and means (21, 21 ', 101") for discharging hydraulic fluid from the piston and the axial passage of the piston rod, while the second spirit of the piston rod terminates on the stone piston surface (5'). 5. Punching machine according to patent claim t 5, can be characterized in that the control rod (23) is provided with a stop (62) for the action of a. electric switch (57), which regulates the circulation of the pressure fluid through the electromagnetic valve (10). Punching machine according to patent claim 10, characterized in that the current switch (57) is connectable (59, 60) connected to the movable parts (1, 2) by a series of sea arms (50, 52, 56), which form a parallelogram. 7. Punching machine according to any one of claims 1-4, and 5-10, characterized in that the control piston (66, 106) is a differential piston, and that its cylinder space (27, 27 ', 27 ") is a differential piston (27, 27', 27"). 85, 107) by means of channels (78, 79) unconnected to the hydraulic circuit by a further control valve (72), so that the sleeve (27 ', 27 ") is displaced towards the valve set (30', 3W ') during standstill of the machine and that the movable parts (101, 102) can be returned under the action of the hydraulic pressure fluid by closing the opening (29, 29 ', 29 ") and by subjecting the piston (66, 106) to a load in order to effect an opening movement of the control sleeve (27 ', 27 "), partly an enlargement of the above-mentioned opening for performing the working stroke or an installation stroke of the movable parts (1, 2) against the stationary machine parts. Punching machine according to any one of claims 1-4 and 5-11, characterized in that the adjusting sleeve (27 ', 27 ") is guided in the axial passage of the piston rod (6', 6") by means of a flange, which is provided with passage passages. (71). for hydraulic pressure fluid. Punching machine according to claim 13, characterized in that a sleeve-like regulating element (90), which serves to reverse the flow of the hydraulic pressure fluid, moves movably inside the axial passage (19 ') of the piston rod (16') and is maneuverable by means of an electromagnet (109). , which is supported by the movable machine parts (1, 2), so that reversal of the flow of the hydraulic pressure fluid can be effected through lamp passages or parts in the cradle of the piston rod (6 '), and that the adjusting sleeve (27') is controlled in the element (90) of a peripheral flange provided with passageways. 10. A punching machine according to claims 13 and 14, characterized in that the piston stitches (6 ') are provided with transverse and longitudinal bores (96 or 97) and together with the element (90) are provided with annular grooves (91, 91') at both the spirits as well as with radial. bores (92, 92 ') and together with the piston rod (6 ") have annular channels (98.99) for the passage of the hydraulic pressure fluid. Punching machine according to claims 14 and 15, characterized in that the electromagnet (109) passes the element (90) through a hose (113) () eh a pin (114) against the pressure frail a spring (93) and is rigidly arranged at the moving parts (2 '). Punching machine according to any one of claims 13-16, characterized in that the cylinder (4 ") of the hydraulic motor is finally connected to a single inlet (102) for supply of hydraulic pressure fluid, which inlet opens into the part (103) of the cylinder (4 "), which is coated next to the smaller surface (5 ') of the piston, so that the return movement of the punch table takes place hydraulically by rearranging the element (90). Request publications: