US3031992A - Metal working press - Google Patents

Description

May 1, 1962 E. K. JOHANSEN 3,031,992

METAL WORKING PRESS Filed June 27, 1956 3 Sheets-Sheet l IN VEN TOR.

EINAR K. JOHANSEN BY ATT'YS FIG.|

May 1, 1962 E. K. JOHANSEN METAL WORKING PRESS 3 Sheets-Sheet 3 Filed June 27, 1956 INVEOR. EINAR K. JOHANSEN United States Patent Ofiice 3,031,992 Patented May 1, 1962 3,031,992 METAL WORKING PRESS Einar K. Johansen, Oak Park, Ill., assignor to US. Industries, Inc., Chicago, 111., a corporation of Delaware Filed June 27, 1956, Ser. No. 594,205 4 Claims. (Cl. 11338) This invention relates in general to metal working or drawing presses and particularly to a mechanically actuated press having a novel form of counterbalancing means associated therewith.

Metal working presses of the general type disclosed herein are customarily provided with a reciprocating slide actuated 'by mechanical means for movement toward and away from the bed of the press for performing a drawing or stamping operation. Where the slide is operated mechanically and is of relatively great size and weight, it is advisable to provide the press with some means for counterbalancing the slide in its downward movement toward the bed.

Heretofore such counterbalancing means have been provided as appendages on the press frame with connections to the slide, and while such means have operated satisfactorily for their purposes, they have required additional space on the frame, thereby requiring additional space which it is necessary for the press to occupy. In addition, earlier counterbalancing arrangements have necessitated the use of extra levers and arms which have increased the cost thereof.

The present invention, therefore, has for its main object to provide a metal working press wherein the counterbalancing means for the slide is more compact and occupies less space and is, therefore, more economical than similar counterbalancing means heretofore known.

Another object of the invention is to provide a metal working press wherein the counterbalancing means for the slide utilizes a cylinder arrangement reciprocable with the slide and a piston therein which is stationary.

A further object of the invention is to provide a metal working press wherein the counterbalancing means includes an air tank either secured to or formed as an integral part of the slide so as to be movable therewith and which has an air cylinder mounted in the tank having a stationary piston therein.

Still another and more specific object of the invention is to provide a metal working press wherein the slide is mounted on a plurality of reciprocating guide rods for movement therewith and wherein an air tank is formed as a part of the slide with a cylinder therein and having a piston within the cylinder mounted on a stationary part of the frame so that the piston is stationary and the cylinder moves with respect thereto during reciprocation of the slide.

Other objects and advantages of the invention will become apparent upon reading the following description taken in conjunction with the accompanying drawings, in which FIG. 1 is a front elevational view of a metal working press embodying the present invention;

FIG. 2 is a side elevational view of the press shown in FIG. 1;

FIG. 3 is a perspective view of a press embodying the present invention, partly in section and with other parts broken away or removed to illustrate more clearly the relationship between the parts and the operation thereof;

FIG. 4 is a fragmentary enlarged vertical sectional view through one of the counterbalancing means showing the slide and the parts attached thereto in the uppermost position thereof, and

FIG. 5 is a view similar to FIG. 4 but showing the slide and its parts in the lowermost position thereof.

The invention herein has been illustrated in the drawings as applied to a single action press although it will be understood that the counterbalancing means, as shown therein, may likewise be applied to the slides of multiple action presses such as the double or triple action type.

The press shown in the drawings for purposes of illustration includes the side frame members 1 and 2 having a bed 3 disposed therebetween, which bed is adapted to have a die member supported thereon. The side frame members are formed, as more clearly shown in FIG. 3, so as to provide a pair of upper guide rod bearing members 4 and 5 at one side and a similar pair of lower bearing members spaced downwardly therefrom, only one of which may be seen in FIG. 3 as indicated by the numeral 6. At the opposite side of the press the frame member 2 is formed to provide similar upper bearing members 7 and 8 and a second pair of lower bearing members, only one of which may be seen in FIG. 3 as at 9.

Guide rods 10 and 11 at one side of the press are received by the upper and lower bearing members for longitudinal sliding movement therein, and at the opposite side of the press similar guide rods 12 and 13 are mounted for longitudinal reciprocating movement in the bearing members on that side of the press.

A slide 14 is suitably secured to the guide rods 10, 11, 12, and 13 so as to reciprocate therewith and to be moved toward and away from the press bed.

A crosshead member 15 is secured to the guide rods 10 and 11 adjacent the lower ends thereof, and a similar crosshead member 16 likewise connects the lower ends of the guide rods 12 and 13 at the opposite side of the press.

The driving mechanism for operating the press and causing reciprocation of the guide rods and slide includes a motor 17 positioned below the bed which drives a clutch and brake arrangement consisting of a clutch member 18 and a brake member 19, both mounted on the main drive shaft 20. Pinions 21 and 22 are mounted on the drive shaft 20 adjacent each end thereof and mesh with gears 23 and 24, respectively, on the driven shaft 25. Pinions 26 and 27 are mounted on the ends of shaft 25 and mesh with gears 28 and 29, respectively, which are rotatably mounted on the crank shafts 3t and 31. Each crank shaft has an eccentric portion 32 intermediate the ends thereof on which is mounted an eccentric disc 33 secured to each of the gears 28 and 29. Con necting rods or links 34 and 35 connect the crank shafts 30 and 31 with the crossheads 15 and 16, respectively, whereby rotation of the crank shaft by the drive means just described will cause the crossheads 15 and 16, the guide rods 10, 11, 12, and 13, and the slide 14 to be raised and lowered in a reciprocating movement.

If desired, the customary cushioning means 36 may be provided below the bed 3 to cushion the impact of the slide 14 thereagainst. The slide 14 is secured to and mounted on the guide rods 10, 11, 12, and 13 by any suitable means but for purposes of illustration, the mounting means disclosed herein includes an adjustable feature so that the slide may be adjusted with respect to the guide rods for varying the distance between the slide and the bed and the pressure exerted thereagainst. Each guide rod is threaded at its upper end, as shown at 37, and has a nut 38 threaded thereon. Each nut 38 has fixed thereto or formed as an integral part thereof a worm gear 39. Each worm gear is in mesh with a worm 40 mounted on the end of a rod 41 so that rotation of a worm will cause its associated worm gear and nut to rotate with respect to the associated guide rod. There being four guide rods, one at each corner of the press, there will likewise be four worm and gear arrangements just described. There will be provided two of the rods 41 with a worm 40 on each end thereof and geared to a drive means 42 so that both rods 41 and all of the worms and worm gears will rotate simultaneously at the same rate of speed. Depending upon the direction of rotation, it will be evident that the slide 14 will thus be raised or lowered with respect to the guide rods.

At each side of the machine the slide 14 is provided with an air tank 43. A cylinder 44 is mounted within each tank 43 at the bottom thereof and has a bottom end 45 having centrally disposed opening 50 therethrough (FIGS. 4 and 5). The upper end of each cylinder 44 is open to the interior of the air tank. An annular space 46 is provided around the cylinder 44 within the tank 43.

A piston 47 is arranged within each cylinder 44 and has a piston rod 48 connected thereto and extending downwardly through the opening 50, the lower end of the rod 48 being securely fixed to a rigid part 49 of the side frame member.

It is thus evident that the piston 47 in each cylinder is fixed to the frame and it is the air tank and cylinder which move with the slide and with respect to the piston during the reciprocating movement thereof.

Thus, as the drive mechanism is operated to move the slide 14 downwardly toward the bed, it will carry with it the air tanks 43 and cylinders 44 fixed thereto, so that in effect the piston 47 will have a relative movement from the bottom to the top of the cylinder from the position thereof shown in FIG. 4 to the position shown in FIG. 5. The cylinder 44 being open at its upper end, the air in the tank will be compressed by this movement and will thereupon counterbalance the slide in its downward movement. As the slide is elevated back to its uppermost position, additional air will be drawn into the air tank to be compressed during the next downward movement of the slide.

In some instances the proper elfect may be obtained by air leaking past the piston and out through the opening in the bottom thereof which is present when the slide is in its lowermost position, as shown at 50. It may be desirable, however, to provide a bleeder hole 51 in the upper part of the air tank 43 if it is determined that such is necessary for the proper operation of the counterbalancing means.

It is thus evident that by forming the air tank as an integral part of the slide itself and maintaining the position of the piston therein stationary at all times, the counterbalancing means consisting of these elements may be made very compact as well as more economical since they become a part of thepress in its original construction rather than being an appendage thereto as heretofore known and used.

Changes may be made in the form, construction and arrangement of parts from those disclosed herein without in any way departing from the spirit of the invention or sacrificing any of the attendant advantages thereof, provided, however, that such changes fall within the scope of the claims appended hereto.

The invention is hereby claimed as follows:

1. A metal working press comprising, a frame having a bed adapted to support a die member thereon, a plurality of guide rods mounted for vertical sliding movement in said frame, a slide secured to said guide rods adjacent the upper ends thereof and adapted to have a die member mounted thereon, whereby reciprocation of said guide rods will move said slide toward and away from said bed for a drawing operation, means for reciprocating said guide rods and slide, and counterbalancing means for said slide including an air tank at each side of said slide movable therewith, a cylinder in each air tank open at its upper end and secured to said 4 tank for movement therewith and communicating through said open end with the interior of said tank, a stationary piston in each said cylinder, and a piston rod connected to each of said pistons and to said frame.

2. A metal working press comprising a press bed including stationary parts, a reciprocable slide movable toward and away from said bed for a drawing operation, means to reciprocate said slide, and counterbalancing means for said slide including an air tank formed as an integral part of said slide at each side thereof and reciprocable therewith, a cylinder having a lower end portion attached to the bottom of each said tank, each cylinder projecting upwardly into a respective tank and being open at its upper end and communicating through said open end with the interior of said tank, a stationary piston in each said cylinder, and means connecting said piston with a stationary part of the press.

3. A metal working press, comprising, a frame having a bed adapted to support a die member thereon, a pair of upper and lower guide rod bearing members integral with said frame at each side thereof, a pair of vertically disposed guide rods at each side of said frame and mounted for longitudinal sliding movement in said bearing members, a slide mounted on said guide rods adjacent the upper ends thereof and adapted to have a die mounted thereon, means adjustably securing said slide to said guide rods formovement therewith toward and away from said bed for performing a drawing operation, a crosshead connecting each pair of guide rods adjacent the lower ends thereof, eccentric drive means at each side of said frame, connecting means between each said crosshead and the eccentric drive means adjacent thereto, whereby operation of said drive means will reciprocate said guide rods and said slide mounted thereon, an air tank at each side of said slide and movable therewith between two of said guide rods, a cylinder in each said air tank open at its upper end and secured to said tank for movement therewith and communicating through said open end with the interior of said tank, a stationary piston in each of said cylinders, and a piston rod for each said piston connected to said frame, whereby movement of said slide toward said bed will cause a relative movement between said tank and cylinder assembly and said piston, thereby compress- :ing the air in said tank and counterbalancing said slide.

4. In a metal working press, a frame, a plurality of guide rods for vertical sliding movementin said frame, a slide secured to said guide rods, meansfor vertically reciprocating said guide rods and slide, and counterbalancing means for said slide including two air tanks disposed outwardly of opposite sides of said slide and in horizontal alignment with the latter, said tanks being attached to said slide and vertically movable therewith, two cylinders, each of said cylinders being open at its upper end and mounted in a respective one of said tanks for movement therewith and communicating through said open end with the interior of said tank, and stationary pistons, each piston being mounted in a respective one of said cylinders and stationarily connected to said frame below said respective cylinder.

References Cited in the file of this patent UNITED STATES PATENTS

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