US3724311A

US3724311A - Construction of mechanical presses

Info

Publication number: US3724311A
Authority: US
Inventors: F Streich; F Ventura; A Gold; J Oliveras
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-03-14
Filing date: 1971-03-11
Publication date: 1973-04-03
Anticipated expiration: 1990-04-03
Also published as: FR2084860A5; SE357699B; GB1349457A; CA934602A; DE2112124A1

Abstract

Improvements in the construction of mechanical presses, comprising a large diameter transverse shaft projecting from the frame of the machine and presenting at its front two crossed slots for housing the sliding carriage of the press and the table of the same, an inertia flywheel in ring form, mounted on said shaft and having on the interior thereof cams for driving the carriage, and driving electric motor positioned between said ring-flywheel and the zone of the frame adjacent to the shaft, the ring-flywheel being connected to the rotor of the motor and the frame being connected to the stator.

Description

United States Patent [1 1 Streich et al.

1 51 Apr. 3, 1973 [54] CONSTRUCTION OF MECHANICAL PRESSES [76] Inventors: Federico Streich, Calaf Street, No. 25; Alberto Vargas Gold, Rosario Street, l9&2l; Jose M Bonastre Oliveras, Menendee Pelavo Street No. 5.3.2; Fernando Fernandez Ventura, San Cugat del Valles, Abella Street, No. 42, all of Barcelona, Spain 22 Filed: Mar. 11, 1971 [21] Appl.No.: 123,178

[50 Foreign Application Priority Data Mar. 14, I970 Spain ..377500 Feb. 25, 197] Spain ..388610 [52] US. Cl. ..83/590, 83/628, 100/292, 100/266, 74/55, 72/76 [51] Int. Cl. ..B26d 5/16 [58] Field of Search ..83l590, 628; 100/291, 292, 100/266; 74/55; 72/76 2/1922 Walsh ..83/590 X Primary Examiner-Gil Weidenfeld Attorney-Woodhams, Blanchard & Flynn [57] ABSTRACT Improvements in the construction of mechanical presses, comprising a large diameter transverse shaft projecting from the frame of the machine and presenting at its front two crossed slots for housing the sliding carriage of the press and the table of the same, an inertia flywheel in ring form, mounted on said shaft and having on the interior thereof cams for driving the carriage, and driving electric motor positioned between said ring-flywheel and the zone of the frame adjacent to the shaft, the ring-flywheel being connected to the rotor of the motor and the frame being connected to the stator.

12 Claims, 10 Drawing Figures PATENTEBAPR3 m5 3. 724,311

'

sum

5 or 5 WW/44x40 i ORNEYS CONSTRUCTION OF MECHANICAL PRESSES This invention refers to improvements in the construction of mechanical presses.

As is known, presses are divided in hydraulic presses and these latter are subdivided in turn in eccentric presses, cam presses and lever presses.

The hydraulic presses are preferentially used in the large tonnage types, by the fact of being slow, and in consequence of low efficiency are displaced by the mechanical presses when these enter in competition as they reach the tonnage levels for which they can be utilized.

The eccentric mechanical presses, which can reach a high number of revolutions per minute, are limited to 500 tons in their utilization owing to the complexity of their transmission system and to the form of their working diagram.

The cam mechanical presses may be adapted to any class of work, nevertheless, due to transmission problems, loss of power in axial efforts, efforts in the keyways, etc., they offer inconveniences the limit their power to a maximum of 100 tons.

The lever presses of which the mostly known is the Rodillera have been economically manufactured up to 1500 tons. However, the problems offered by the inertia flywheel, clutch and transmissions, render it uneconomical for higher powers.

The object of the invention has been to obtain a mechanical type press without the previously mentioned difficulties, but with the advantages of the hydraulic presses, or without working tonnage limits and with similar working speeds to the mechanical presses.

The object of the invention is essentially a new design of press that allows that application of a series of devices that fulfill the following postulates:

a. The motor is directly coupled to the inertia flywheel without any intervening structure.

b. The inertia flywheel directly joins the structure that transforms the rotary movement of the flywheel into a lineal one, which is applied onto the carriage of the press.

C. The machine table is so relationed with the carriage, that constituting a single incorporated whole, may be distanced the one from the other, losing contact with the structure destined to transform the rotary .movement of the flywheel into a lineal one, said distancing constituting the act of declutching and braking; and inversly, or nearing or approaching, the act of unbraking and clutching.

d. The shaft or the principal shafts of the machine will have a velocity convenient to perfect functioning of their bearings, in spite of the slow running of the machine.

e. Upon increasing the power of the machine, the loads on the principal shafts are conserved at a value perfectly compatible with the normal working conditions.

Bearing in mind the foregoing postulates, a press has been constructed in which the power transformations are effected without the transmission of vibrations in the working mechanisms, which is obtained by situating the motor and the power transmission and the transformation structure within the same single plane, for which the inertia flywheel forms part of the rotor of the motor, and at the same time is carrier of the profile of the cam, which profile permits the maximum advantage of the carriage movements to be taken.

In order to obtain inertia flywheels appropriate for the new type of press, the flywheel has been conceived in the form of a large diameter ring, the larger the greater the working tonnage of the machine, with the cam mounted on the inner circle of the ring, eliminating excessive axial components and without the necessity of levers and keyways.

Moreover, owing to the large diameter of the cam carrier flywheel, and with the object of the increasing the number of blows per minute, it is possible to utilize the whole of the circular periphery of the flywheel, more than one cam being provided in same, in order to repeat as many working cycles as there are cams in the flywheel during each complete rotation, or it is possible also to study the form of cam to make the fullest possible use of the dead points, or of passive working of the machine.

This press oflers, moreover, a high resistance to and practically a total lack of transmission friction which brake its potency, so that its power capacity is very high even at great tonnages, which is attained because the flywheel is an integral part of the driving motor itself, without any intermediate transmission structures, moreover, as element on which the flywheel turns that actuates consequently as axis, the framework itself of the machine is found, of such a capacity to house the table of the press and at the same time the carriage of same, so that the resistance of the machine is much higher than that of conventional presses.

As a complement and between the axis of rotation of the flywheel and this latter are situated the rotary structures whose specific mission is to center the flywheel and distribute the loads.

The press clutch system has been solved by joining the carriage and the table in elastic form with an upper stop and with the table held floating by means of pistons, so that unloading tends to separate the table and the carriage from contact with the cam.

In order to facilitate the explanation, sheets of drawings are included with this specification showing one case of realization as an example only. In the drawings:

FIG. 1 is a front elevation of the press as in the invention.

FIG. 2 is a cross section of side elevation of the press,

FIG. 1.

FIG. 3 is a side elevation of the inertia flywheel in ring form.

FIG. 4 is a front elevation of the flywheel from the exterior.

FIG. 5 is a front view of the rocking cradle housed in the upper face of the movable carriage and displaceable by the cam.

FIG. 6 is a side view of the rocking cradle of the FIG.

FIG. 7 is a front view of the two lower rocking cradles.

FIG. 8 is a front elevation of the clutch device in in position".

FIG. 9 is a front elevation of the clutch in declutched position.

FIG. 10 is a sectional detail of the punch and punchholder in FIGS. 3 and 4 in the declutched position.

Referring to the figures, the press comprises an inertia flywheel 1 in the form of a ring of adequate weight for the power of the machine, whose large interior diameter houses the stationary axle or shaft 2 of large proportions. The flywheel is rotatably supported on axle 2 by means of a series of rollers 3 at the lower half part mounted on rocking cradles 4, and another series of tension rollers 5 at the upper half part, held elastically against the ring.

The mentioned

rollers

3 and 5 radially support the flywheel whereas

further rollers

7 and 8 engage the opposite axial sides of the flywheel, the rollers 7 being mounted on the shaft 2 and the rollers 8 being mounted on the frame 9 of the machine, the shaft 2 and the frame 9 being integral the one with the other.

A rotor 10 of an electric motor is provided on the flywheel itself, while a stator 11 is fixed to the frame 9 precisely at the beginning of the shaft 2.

The flywheel 1 has one or more cams 12 that drive a carriage 13 which is slidably supported in a radial slot 41 formed in shaft 2. Owing to the large interior diameter of the flywheel, the cams occupy arcs of substantial length, in consequence of which the angles of the slopes of same are of very low value. Carriage 13 has rollers 14 mounted thereon which are engaged by the cams 12.

A table 15 of the machine is disposed in a further slot 42 formed in shaft 2 and is connected with the carriage 13 through an elastic system which also functions as extremity stops. The elastic system includes ears 16 projecting from the carriage which are pierced by rods 17 fixed to the table 15, and over said rods elastic elements or springs 18 are positioned between the table and the ears 16. The movement between carriage 13 and table 15 is limited by nuts 19 at the extremities of the rods 17, and the engagement of the lower extremities of the carriage on the table. The carriage 13 and table 15 permit a pressing operation to be performed on a workpiece located therebetween due to movement of the carriage 13 by the rotation of the cam 12.

The table 15 is held in position by pins 20 which are fixed to shaft 2 and extend into suitable recesses in the table, the table 15 being held against the pins by pistons 21.

The carriage 13 is guided within the vertical slot 41 in the shaft, while the table 15 and pistons 21 are housed in the transverse slot 42, both slots forming between them a cross cavity.

In FIGS. 3 to 7, 7 represents each one of the three rollers distributed on the front face 1a of the flywheel 1, which may be adjusted to obtain a more regular running of the flywheel 1, by fixing them in the most convenient position; and 8 represents each of the three rollers, duly distributed on the rear face 1b of the flywheel. A rocking cradle 22 is housed in the upper face of the carriage 13 of the press, and has two parallel cylindrical rollers 14 mounted thereon for transmitting the effect of the cam 12 to the carriage 13. A spherical helmet 23 rockingly supports said cradle 22 on the carriage 23. The pair of upper tension rollers are urged by springs 27 into engagement with flywheel 1, thus maintaining the flywheel against the rollers 3 mounted on the lower rocking cradles 4. The cradles 4 are supported on pivot pins 38 which project from shaft 2.

FIGS. 8 to 10 illustrate a variation of the carriage, same having been designated 13'. The carriage 13' includes an upper member 26 which is engaged by the cam 12 and whose lower base is an inclined plane which is supported on the upper plane of the wedge 28 which is slidably supported in the guide plate 29. A holding stop 30 and a pressure stop 31 position the wedge 28.

A punch carrier sleeve 32 that has a toothed interior engages by rotation with the exterior teeth of the punch 33 that projects from the plate 29 toward the press table 15. A vertical shaft projects from the horizontal and lower plane of the wedge 28, which shaft is housed in the lengthened slot 36 presented by the

intermediate guide plate

29 and 37 is a short horizontal shaft displaceable by the vertical shaft 35. P is the force transmitted by carriage 13 through distance h, and F is the force that pushes the wedge 28 toward the stop 30.

The rotation of the flywheel with a radial and axial guide system by means of rollers, presupposes a mechanism of high precision, and this has been avoided due to the conveniently distributed rollers 7 on the front face, while on the back face other rollers 8 are applied of equal form, duly distributed, adjustable and fixable in the most convenient position, constituting elastic forces by both groups of rollers that are tensed and mutually compensated.

The conjoint assembly of

elements

26, 29, 28 and 32 transmit the force P through the distance h on to the table 15, and the wedge 28 maintains its position in the direction of the force F toward the stop 30. In the displacements of the wedge 28, this transports the lower vertical shaft 35 that promotes the rotation of the toothed plunger 33, that couples with the punch carrier sleeve 32, increasing the height h, disconnecting itself from the table 15, which is equal to a declutching all of which with the intervention of the short horizontal shaft 37, against the axis 35 housed in the lengthened slot 36.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Improvements in the construction of a mechanical press, comprising a frame, a large diameter transverse shaft projecting from said frame and presenting at its front two crossed slots, a carriage slidably positioned in one of said slots and a table disposed in the other slot opposite said carriage, and an inertia flywheel in the form of a ring rotatably supported on and surrounding said shaft, said flywheel having at least one cam thereon disposed for engagement with said carriage for slidably moving said carriage within its slot when said flywheel is rotated relative to said shaft, and driving electric motor means coacting between said flywheel and said frame for causing rotation of said flywheel relative to said frame, said motor means including a rotor fixedly connected to said flywheel and a stator positioned adjacent said rotor and fixedly connected relative to said frame.

2. Improvements according to claim 1, including roller means coacting between said shaft and said flywheel for rollingly supporting said flywheel on said shaft.

3. Improvements according to claim 2, wherein said roller means includes a pair of resiliently urged rollers coacting between said shaft and the upper half of said flywheel.

4. Improvements according to claim I, further including roller means coacting with the opposite axial end faces of said flywheel for counteracting the axial forces imposed on said flywheel.

5. Improvements according to claim 1, further including roller means rotatably supported on said carriage and positioned for rolling engagement with said cam.

6. Improvements according to claim 1, further including elastic means operatively connected-between said carriage and said table for permitting limited linear movement of said carriage relative to said table while enabling said carriage to be moved only a predetermined distance away from said table.

7. Improvements according to claim 6, further including means for normally fixedly maintaining said table in a stationary position relative to said shaft, and means normally maintaining said table in said stationary position while enabling said table to be floatably moved relative to said shaft to enable said table and carriage to be moved in a direction away from said cam.

8. Improvements according to claim 1, wherein said one slot extends substantially radially of said shaft and said carriage is slidable linearly therealong in a direction substantially radially of said shaft, said carriage having cradle means pivotally supported thereon adjacent to the radially outer end thereof, said cradle means having roller means rotatably supported thereon and disposed for engagement with said cam whereby rotation of said flywheel causes said cam to engage said roller means for causing inward radial displacement of said carriage along said one slot, said carriage being radially displaced inwardly toward said table.

9. Improvements according to claim 8, further including a plurality of circumferentially spaced lower cradles pivotally supported on said shaft, each of said lower cradles having a pair of spaced cylindrical rollers rotatably supported thereon and disposed for rolling engagement with the inner peripheral surface of said flywheel, and resiliently urged tension roller means coacting between said shaft and the upper half of said flywheel for normally resiliently urging said flywheel upwardly relative to said shaft for maintaining the inner peripheral surface of said flywheel in rolling engagement with the cylindrical rollers mounted on said lower cradles.

l0. Improvements according to claim 1, wherein said rotor of said motor is fixedly secured to one axial end of said flywheel, and said stator being fixedly secured to said frame directly opposite said rotor and in surrounding relationship to said shaft substantially adjacent the junction of said shaft and said frame.

11. Improvements according to claim 1, wherein said one slot extends substantially radially of said shaft with the outer end of said slot terminating at the outer periphery of said shaft, and said other slot extending substantially perpendicular to said one slot adjacent the radially inner end thereof, said other slot projecting radially outwardly on opposite sides of said one slot but having the ends thereof terminating short of the periphery of said shaft.

12. Improvements according to claim 12, wherein said shaft projects substantially horizontally, wherein said one slot extends vertically and radially upwardly so as to pro ect through the upper surface of said shaft,

and wherein said other slot extends substantially horizontally, said pair of slots having a substantially inverted T-shaped configuration.

Claims

4. Improvements according to claim 1, further including roller means coacting with the opposite axial end faces of said flywheel for counteracting the axial forces imposed on said flywheel.

6. Improvements according to claim 1, further including elastic means operatively connected between said carriage and said table for permitting limited linear movement of said carriage relative to said table while enabling said carriage to be moved only a predetermined distance away from said table.

10. Improvements according to claim 1, wherein said rotor of said motor is fixedly secured to one axial end of said flywheel, and said stator being fixedly secured to said frame directly opposite said rotor and in surrounding relationship to said shaft substantially adjacent the junction of said shaft and said frame.

12. Improvements according to claim 12, wherein said shaft projects substantially horizontally, wherein said one slot extends vertically and radially upwardly so as to project through the upper surface of said shaft, and wherein said other slot extends substantially horizontally, said pair of slots having a substantially inverted T-shaped configuration.