MECHANICAL PRESS

Description

Field of the invention

[0001] The present invention relates to a mechanical press according to claim 1.

Background of the invention

[0002] RU 2 019 416 C1 discloses a vertical mechanical press containing an activating electromagnet being mounted between brackets on the front side part of an upper elbow of a connecting rod with a stator-cylinder rotating about its axis, wherein the stator-cylinder is coupled with a lower elbow of a collapsible connecting rod through double-linked collapsible lever of a transfer mechanism, wherein the length of the collapsible lever may be regulated and wherein both brackets have through windows disposed above the stator journals. Lower sleeves of return springs of the magnet anchor are rigidly secured to bracket bodies above the windows.

[0003] SU 651 532 A discloses a mechanical press comprising a slide placed in guide rails of a machine bed, wherein the slide is coupled to a crank shaft through a two-link rod having an upper and a lower elbow, wherein the press further comprises a frame coupled to the slide, a transfer mechanism and an electromagnetic press actuating mechanism arranged in the frame. The transfer mechanism is made in the form of hingedly connected levers and battens connecting armature of the electromagnet with the lower elbow of the two-link rod.

[0004] The mechanical press is known, having a slide placed in bed guide rails, the slide is coupled to a crank shaft or eccentric shaft through a two-link rod and is tied with cylindrical balancers fixed to a bed; an electric motor is mounted on a machine bed and is connected through a flexible drive with a flywheel fixed rigidly on the above shaft; a slide has upper working position limit stop. Besides, the press has a clutchless press actuating mechanism, installed on the bed, controls for a clutchless mechanism as well as a transfer mechanism made as a balancing lever, connected by a hinge with a two-link connecting rod ( DE 561059C, 1934-03-19, IPC B30B1/26).

[0005] The shortcomings of this mechanical press are its lower reliability, service life and productivity due to an alternate / reciprocal motion of the piston together with a connecting rod inside a pneumatic or hydraulic cylinder of a clutchless actuating mechanism during press operation, as a result of this the clutchless mechanism works as an air pump that results in a quick wear of a piston and a cylinder connecting rod lip-type seals and in unjustified energy losses of a machine drive.

[0006] At the same time, at each press slide travel from the extreme upper to the extreme lower position the so called "squeezing" of the compressed air (or liquid) occurs inside the actuating cylinder connecting rod cavity, and a power friction takes place simultaneously in a cylinder hinge and in a hinge of a two-link connecting rod, thus causing additional energy losses which reduce press output and its service life.

[0007] Besides, a mass of the actuating cylinder mechanism fixed to a hinge and protruding as a cantilever outside the machine bed zone will increase a value of dynamic loads applied to connecting rod links of a press crank group and on its bed due to alternating up and down swinging on a hinge.

[0008] Then, during an axle rotation when compressed air (or liquid) enters into the connecting rod cavity of the cylinder piston, the piston and the connecting rod will move to the right at the command of the press actuating mechanism.

[0009] At this time, as it was found in our experimental investigations, the connecting rod upper link 7 with a stop 12 and a connecting rod lower link 8 with a stop 13 are also moving to the right direction till the moment of an impact of both stops 12 and 13, to ensure a fixed position of connecting rod links 7 and 8 during operation (numbers on these positions correspond to positions in the drawings of the above patent).

[0010] Dynamic impacts and concussions of the press drive during its operation in a single stroke mode at a maximum rate reach 40 - 50 strokes/min.

[0011] All these conditions cause increased loads on all parts and units of the machine and as a result of this a reliability, service life and safety of both the clutchless actuating mechanism and a mechanical press as a whole are reduced.

[0012] In addition to this the aerosol mixture of oil with compressed air is being discharged into the atmosphere from a cylinder of the actuating mechanism at each slide stroke during operation in a single stroke mode, thus deteriorating ecological conditions inside the room.

[0013] A mechanical press is also known which has a slide placed in bed guide rails, the slide is coupled to a crank shaft or eccentric shaft through a two-link rod and is tied with a balancer fixed to a bed; it has a limiter of a slide upper working position and also an electric motor located on a bed and connected through a flexible drive with a flywheel fixed rigidly on the shaft. Besides, the press has a clutchless press actuating mechanism, installed on the bed, controls for a clutchless mechanism as well as transfer mechanism made as a balancing lever, connected hingedly with a two-link connecting rod ( CZ135097, 1969-07-04, IPC B30b).

[0014] The shortcomings of this press known by the Patent of Czechoslovakia are its insufficient reliability and service life caused by the action of the crankshaft during press operation onto a movable wedge stop 13 of a clutchless actuating mechanism through a rod 10 and a moving bar 11 with a wedge limiter 11a, this causes skewing of a wedge stop 13 of a control mechanism 14 inside bed guide rails 1 and this leads to a breakage of a transfer mechanism as it was shown by our experimental investigations. Apparently, the wedge stop 13 of the actuating mechanism 14 can not move down simultaneously during a slide movement from its upper position into its extreme lower position to compensate a crank mechanism travel during rotation of a crankshaft due to its jamming inside press guide rails caused by skewing.

[0015] Moreover, when a moving wedge stop of the clutchless actuating mechanism travels down, high frequency noise exceeding 90 dB is generated at each actuation of a press in a single stroke mode (40-50 strokes per minute) due to strong impacts between the rod wedge stop and the actuating mechanism wedge stop. This noise leads to a detrimental effect on a health of the press service personnel and does not correspond to accepted operator safety norms during mechanical press operation.

[0016] Besides, in the mechanical press by the above Patent of Czechoslovakia the agent in the actuating cylinder is also being "squeezed" during each slide travel and a power friction occurs in rod hinges and in guides of the moving bar. This causes additional energy losses which decrease the press output and its service life.

[0017] A mechanical press is known which is taken as a closest counterpart, comprising a slide placed in bed guide-rails, the above slide is connected with a crank shaft or eccentric shaft through a two-link rod and is tied with a cylindrical balancer fixed to a bed and to an elastic limiter of a slide upper position located in the above balancer and also an electric motor located on a bed and connected through a flexible drive with a flywheel fixed rigidly on the shaft, electromagnetic clutchless press actuating mechanism in a form of at least, one electrical magnet, consisting of a body and a movable armature, a transfer mechanism in a form of a balancer connected through a hinge with a two-link rod and also press controls. ( SU 745705A, IPC B30B1/26, 1980-07-07; and also GB 1578373A, 1980-11-05, IPC B30B15/00, B21D22/00, B21D28/00, B21J11/00, B23D15/00). GB 1578373 A disclose a mechanical press according to the preamble of claim 1. In the said mechanical press a design of a slide is foreseen which consists of two interconnected adjustable parts (lower and upper part), the above design impairs and complicates press service conditions during its maintenance.

[0018] Besides, in the said mechanical press design the electrical magnet of the press clutchless actuating mechanism is located directly on a slide and as a result of this the said mechanism receives all dynamic loads (shocks, concussions, vibrations, oscillations) generated as a result of a slide work during cold sheet operations: cutting down, punching, cutting, bending, etc., that also reduces reliability, longevity and service life of a press actuating mechanism.

[0019] Moreover, a power contact between a cone and a flag/balancer 47 of a two-link rod takes place at a magnetic action on command in both electromagnets of the armature 36 with a coil 35 of the body 34.

[0020] Technological difficulties of manufacturing a clutchless mechanism arise at production of this press and these are caused by obtaining many precise mating surfaces: the armature 36 with a surface of the body 34 outer face; a core 45 with the opening 40 of the disc 39; a cone 41 with a conical opening 48 of the balancer 47, this complicates a press design and increases its cost.

[0021] Besides, the design of the second version of this press according to the above patent of Great Britain, illustrated in Fig. 3 and 4, foresees an interaction of the armature 36 with the surface of the body 34 outer face as well as simultaneous interaction of friction elements 49 of the moving discs 50 with face surfaces of the flag/balancer 47 of the press connecting-rod. As it was shown by our experimental investigations, formation of gaps between these elements and the flag/balancer 47 takes place in case of the frictional elements 49 wear and the force retention of links of the two-links rod in the required position discontinues, that causes emergency situation during operation of the mechanical press.

[0022] Thus, both design versions of the clutchless electromagnetic actuating mechanisms as by SU745705 and by GB1578373 do not correspond to a full extent to safety requirements and operation conditions of mechanical presses.

Summary of the Invention

[0023] The technical objective of the invention is to increase a reliability, longevity and productivity of a press, to prolong its service life, to improve ecological cleanness and safety requirements during press operation.

[0024] To solve this problem a mechanical press according to claim 1 is proposed.

[0025] In this case it is expedient to make the slide initial upper position limiter in the form of a rod protruding from a piston in the upper cavity of the balancer cylinder. An elastic ring with a through hole is mounted freely on this rod.

[0026] The best results can be achieved if the elastic ring of the slide initial upper position limiter will have thickness larger than the length of rod protruding from the piston by the value of the damping gap.

Brief description of the drawings

[0027] 

Fig. 1 shows a sectional view of the mechanical press

Fig. 2 shows a sectional view of the mechanical press along line A-A on Fig 1.

Fig. 3 shows a sectional view of the mechanical press along line B-B on Fig. 1.

Fig. 4 shows a sectional view of the mechanical press along line B-B on Fig. 1

The best example of the invention realization

[0028] The best design version of the proposed mechanical press is given further but all possible realization versions of the proposed invention are not limited by it.

[0029] The mechanical press (Fig.1) has a slide 3 placed in guide rails of a machine frame 1 and connected with a balancer 2 installed on a machine bed, the said slide is coupled to a crank shaft or eccentric shaft through a two-link rod 5 with an upper 5 and lower 7 elbows.

[0030] The electric motor mounted on a machine frame 1 is connected by a flexible drive with a flywheel (they are not shown on Fig. 1 - 4), the flywheel is fixed rigidly on a crankshaft or eccentric axis 4.

[0031] A press clutchless electromagnetic actuating mechanism consists of an electromagnet 8, installed on a machine frame 1, the said electromagnet comprises a body 9 with an electromagnetic coil 10 with a core 11 inside it, a movable armature in the form of a two-arm lever 12, fixed with a possibility to rotate on the axis 13, the said axis is mounted on a press bed. Here one arm 14 of the movable armature - two-arm lever 12 (see Fig. 1), located at a side of a press bed wall, is placed to ensure coupling with a platform 18 of a fixed core 11 of the electromagnetic coil 10 of the body 9 of the electromagnet 8. This coupling possibility is realized with the help of the movable adjustable core 16 having a platform 17 placed in a lever.

[0032] Another arm 19 of the movable armature - two-arm lever 12 is movably connected via the axis 20 to the external end of the drive mechanism balancing lever 21 which is hingedly connected by its opposite end through the axis 22 with a two-link rod 5.

[0033] A slide upper working position limiter is made for example, from rubber in the form of an elastic ring 23 with a central through hole and the said ring is located loosely on a free end 25 of a rod 26 protruding from a balancer 2 of a piston 24 in the upper cavity of the balancer 2 cylinder 27. Here the thickness of the elastic ring 23 is larger than the protruding from a piston 24 the end 25 of a rod 26 by the size of the damping gap. The piston 24 loaded by a spring 28 and a rod 26 are connected through an axis 29 and brackets 30 with a slide 3.

Mechanical press operates in the following way.

[0034] A crankshaft 4 starts rotating in a usual way (with the help of a flexible drive and a flywheel) at starting an electric motor mounted on machine frame 1, when a crank begins to rotate in the opening of the upper elbow 6 of a two-link connecting rod 5.

[0035] Under the action of a rotating axis 4 of a crank at energizing coil 10 of the electromagnet 8, the elbows 6 and 7 of a two-link rod 5 are "folding" and start making swinging motions around a middle arm pivot of a connecting rod 5. A slide 3 is kept in this case in the extreme upper position with the action of a spring 28 of the balancer 2 through a piston 24, a rod 26, axis 29 and brackets 30. The slide upper position is defined by the interaction of a piston 24, an elastic spring 23 and a bottom of a cylinder 27 of a balancer 2.

[0036] A movable armature - two-arm lever 12 together with a spring 15, core 16 and a platform 17 mounted in the said lever makes free swinging motions around axis 13 from the extreme left to the extreme right position as a result of action of rocking links 6 and 7 of the connecting rod 5 through the axis 22, balancer 21 and axis 20 onto an inner arm 19 of the movable armature - two arm lever 12.

[0037] To start a mechanical press operation on a command from a control unit (not shown on Fig. 1-4) when a crankshaft 4 is in its upper position, it is done in a usual way by putting a voltage to a coil 10 of the electromagnet 8. At this moment the outer arm of the movable armature - two arm lever 12 occupies its extreme left position (as shown on Fig. 1), while a movable platform 17 of a core 16 is positioned in the vicinity of a platform 18 of the fixed core 11 belonging to an electromagnetic coil 10 of the electromagnet 8 body 9. As a result of a voltage supplied to the electromagnetic coil 10, its platform 17 moves down and is pulled to and interacts with the surface of the platform 18 of the core 11 of the electromagnetic coil 10. This causes compression of a restoring coil 15 which results in a locking of a movable armature - two-link lever 12 by a surface of a platform 18 of the electromagnetic coil 10 core 11. At this time the return spring 15 is compressed which results in locking of a moving armature - two-arm lever 12 in a fixed position so that it can not turn around the axis 13. As a result of this the elbows 6 and 7 of the connecting rod 5 are fixed in a required straightened position.

[0038] At further rotation of the crank of the shaft 4 the slide 3 starts moving in the lower position and makes a work operation. Moving parts of a balancer 2 are moving together with a slide 3. All parts return back to initial position at power cut a coil 10 of the electromagnet 8. After this a cycle is repeated.

[0039] The proposed invention enables to increase press reliability, longevity and output as well as to prolong its service life and simplify maintenance during operation.

[0040] In addition to these optional improvements concerning design of the slide upper working position limiter, indicated at page 7, lines 21-28 of description of the present invention, it will improve safety of the mechanical press in operation. Thus a simple and easy access construction of the proposed mechanical press with a new design of a clutchless press actuating mechanism ensures complete ecological cleanliness of the environment around this press.

Industrial applicability

[0041] This invention can be applied to manufacturing of new press and forge equipment and other types of machines with a crankshaft mechanism and can also be used for rebuilding various models and types of older press and forge machines in current operation.

Claims

1. A mechanical press comprising

- a slide (3) placed in guide rails of a machine bed (1), wherein the slide (3) is coupled to a crank- or eccentric shaft (4) through a two-link rod (5) and connected to a cylindrical balancer (2) fixed to the machine bed (1), wherein in the cylindrical balancer (2) is arranged a limiter (23) of upper position of the slide (3),

- an electric motor mounted on the machine bed (1) and connected through a flexible drive with a flywheel rigidly fixed on the shaft (4),

- an electromagnetic clutchless press actuating mechanism in the form of at least one electromagnet (8) which consists of a body (9) and a moving armature,

- a transfer mechanism in the form of a lever (21) hingedly connected to the two-link rod (5), and

- press control means, -

characterized in that
the moving armature of the electromagnet (8) of the electromagnetic clutchless press actuating mechanism is made in the form of a two-arm lever (12) rotatably mounted on the axis (13) fixed to the machine bed (1),
wherein one arm (14) of the two-arm lever (12) located at the side of the machine bed wall, is mounted to be mated with the electromagnet (8) by means of a movable spring-loaded adjustable core (16) with a platform (17), and
wherein the other arm (19) of the two-arm lever (12) is movably connected to the outer end of the lever (21) of the transfer mechanism.

2. Mechanical press according to claim 1, characterized in that the limiter of an initial upper position of the slide (3) is carried out as a rod (25) protruding out of a piston (24) in a cylinder cavity located over the piston (24) of the balancer (2), wherein an elastic ring (23) with a through hole is freely mounted on the protruding rod (25).

3. Mechanical press according to claim 2, characterized in that the elastic ring (23) of the limiter of the initial upper position of the slide (3) has a thickness larger than a length of the rod (25) protruding from the piston (24), to a size of a damping gap.

Ansprüche

1. Mechanische Presse mit

- einem in Führungsschienen eines Maschinenbetts (1) angeordneten Schlitten (3), wobei der Schlitten (3) mit einer Kurbelwelle oder exzentrischen Welle (4) über eine zweigliedrige Stange (5) gekoppelt ist und mit einer zylindrischen Ausgleichseinrichtung (2) verbunden ist, die an dem Maschinenbett (1) befestigt ist, wobei in der zylindrischen Ausgleichseinrichtung (2) ein Begrenzer (23) für eine obere Position des Schlittens (3) angeordnet ist,

- einem Elektromotor, der an dem Maschinenbett (1) angebracht ist und über einen flexiblen Antrieb mit einem fest an der Welle (4) befestigten Schwungrad verbunden ist,

- einem elektromagnetischen kupplungslosen Pressenbetätigungsmechanismus in Form wenigstens eines Elektromagnetes (8), der aus einem Gehäuse (9) und einem Bewegungsanker besteht,

- einem Übertragungsmechanismus in Form eines gelenkig mit der zweigliedrigen Stange (5) verbundenen Hebels (21) und

- einer Pressensteuereinrichtung

dadurch gekennzeichnet, dass
der Bewegungsanker des Elektromagnets (8) des elektromagnetischen kupplungslosen Pressenbetätigungsmechanismus in Form eines zweiarmigen Hebels (12) ausgeführt ist, der drehbar auf der an dem Maschinenbett (1) befestigten Achse (13) angebracht ist,
wobei ein Arm (14) des zweiarmigen Hebels (12), der an der Seite der Maschinenbettwand angeordnet ist, so angebracht ist, dass er mit dem Elektromagnet (8) über einen bewegbaren federbelasteten einstellbaren Kerns (16) mit einer Plattform (17) in Eingriff steht, und
wobei der andere Arm (19) des zweiarmigen Hebels (12) bewegbar mit dem äußeren Ende des Hebels (21) des Übertragungsmechanismus verbunden ist.

2. Mechanische Presse nach Anspruch 1, dadurch gekennzeichnet, dass der Begrenzer einer anfänglichen oberen Position des Schlittens (3) als eine Stange (25) ausgeführt ist, die aus einem Kolben (24) in einem über dem Kolben (24) der Ausgleichseinrichtung (2) angeordneten Zylinderraum vorsteht, wobei ein elastischer Ring (23) mit einer Durchgangsöffnung frei an der vorstehenden Stange (25) angebracht ist.

3. Mechanische Presse nach Anspruch 2, dadurch gekennzeichnet, dass der elastische Ring (23) des Begrenzers der anfänglichen oberen Position des Schlittens (3) eine Dicke aufweist, die größer ist als eine Länge der Stange (25), die aus dem Kolben (24) vorsteht, um eine Dämpfungslücke zu dimensionieren.

Revendications

1. Presse mécanique comprenant :

- un coulisseau (3) placé dans des rails de guidage d'un banc de machine (1), dans laquelle le coulisseau (3) est couplé à un vilebrequin ou arbre d'excentrique (4) par le biais d'une bielle à double liaison (5) et connecté à un équilibreur cylindrique (2) fixé sur le banc de machine (1), dans laquelle un limiteur (23) de position supérieure du coulisseau (3) est disposé dans l'équilibreur cylindrique (2),

- un moteur électrique monté sur le banc de machine (1) et connecté, par le biais d'un entraînement flexible, à un volant fixé de manière rigide sur l'arbre (4),

- un mécanisme électromagnétique d'actionnement de presse sans embrayage sous la forme d'au moins un électro-aimant (8) consistant en un corps (9) et une armature mobile,

- un mécanisme de transfert sous la forme d'un levier (21) connecté de manière articulée à la bielle à double liaison (5) et

- un moyen de commande de presse,

caractérisée en ce que
l'armature mobile de l'électro-aimant (8) du mécanisme électromagnétique d'actionnement de presse sans embrayage est réalisée sous la forme d'un levier à deux bras (12) monté de manière rotative sur l'axe (13) fixé sur le banc de machine (1),
dans laquelle un bras (14) du levier à deux bras (12) situé sur le côté de la paroi du banc de machine est monté de manière à être accouplé à l'électro-aimant (8) au moyen d'un noyau réglable chargé par ressort mobile (16) pourvu d'une plate-forme (17) et
dans laquelle l'autre bras (19) du levier à deux bras (12) est connecté de manière mobile à l'extrémité extérieure du levier (21) du mécanisme de transfert.

2. Presse mécanique selon la revendication 1, caractérisée en ce que le limiteur d'une position supérieure initiale du coulisseau (3) est exécuté en tant que tige (25) saillant à l'extérieur d'un piston (24) dans une cavité de cylindre située au-dessus du piston (27) de l'équilibreur (2), dans laquelle une bague élastique (23) pourvue d'un trou de passage est montée librement sur la tige saillante (25).

3. Presse mécanique selon la revendication 2, caractérisée en ce que la bague élastique (23) du limiteur de la position supérieure initiale du coulisseau (3) a une épaisseur plus large qu'une longueur de la tige (25) saillant hors du piston (24), d'une dimension d'une fente d'amortissement.

Drawing