Патент USA US2113311код для вставки
April 5, 1938. F. J. RODE TEMPERATURE CONTROL FOR HYDRAULIC CUSHIONS Filed March 12, 1935 ' 2,113,311 Patented Apr. 5, ‘1938 2,113,311 UNITED STATES PATENT OFFICE 2,113,311 TEMPERATURE CONTROL FOR HYDRAULIC CUSHIONS Fredrick J. Bode, Toledo, Ohio Application March 12, 1935, Serial No. 10,747 2 Claims. (Cl. 100-71) This invention relates to power presses and is more particularly directed to a press having a‘ hydraulically cushioned pressure pad. The primary object of the invention is the pro vision of means to increase the operating capac ity of the press by controlling the working tem perature of the liquid used to cushion the pres sure pad, so as to increase the possible length of stroke of a press operating ata given speed, or 10 to increase the number of strokes per minute which can be attained by a press having a given slide travel. - Other objects and advantages of the invention will become apparent as the description proceeds, 15 reference being had to the accompanying draw ing which illustrates one embodiment of the in vention and in which— Figure l is a diagrammatic side view of a press with the pad and cushion parts in section; Fig. 2 20 is a detail elevation of one of the temperature control coils; Fig. 3 is an end view of the coil taken on line 3-3 of Fig. 2; and Fig. 4 is a sche matic arrangement of the circulating system for the temperature control medium. 25 Referring to the drawing, my invention is shown in connection with a press l'having a sta tionary bed 3. A centrally disposed pressure pad 5 is provided in the path of travel of the main slide of the press in a manner well known in the 30 art. The pressure pad is carried at the upper end of a stem 1 which carries a piston 9 at its lower end for controlled reciprocation in a cush ion cylinder II. The cushion cylinder is adapted to be ?lled with oil or other suitable liquid from 35 a surrounding reservoir I3 through a centrally closing the valve _-n and holding the parts until the main forming die (not shown) has completed substantially a half of its up-stroke, thereby pre ' venting deformation of the formed metal by reason of a premature raising of the pressure pad. 5 The valve I1 is then opened and oil from the res ervoir I3 is forced into the cylinder by air pres'— sure. It will be seen that'the ?ow of the oil past the valve i1 is thus extremely rapid in both di 'rections so that the friction encountered is suf- 10 ?ciently great to raise the oil temperature to ' such a point that in some installations the pack ing has been burned from the piston 8, and other damage has been done. To overcome this condi tion it has been the practice to limit the length 15 of stroke of a press operating at a given speed, and similarly to restrict the number of strokes per minute of a press having a given length of stroke. It will ‘be appreciated that the velocity of the oil through the passage l5 depends on 90 these factors, and hence the temperature rise of the oil is similarly dependent. In order to increase the working capacity of the press, and permit an increase in operating speed _ of a press having. a given length of stroke, the 35 present invention provides means, to control the working temperature of the oil used in the hy draulic cushion. This means preferably includes metallic ‘coils 25 disposed-in the bottom .of the reservoir l3 and constantly immersed in the liq- 30 uid. The coils may be made of any‘ suitable ma terial and may be of any vdesired thickness, de pending on the co-ef?cient of heat conductivity valve may be operated in any suitable manner, of the material used. The coils are preferably helical in form so as to-expose the maximum sur- 35 face in a'minimum lateral area. At each end the coil is brought out through the wall of the reservoir to connect with‘ ‘a suitablev union- 2'! fixed to ‘the reservoir. 2| working in a cylinder [9. The piston I9 is movable in either direction by air pressure either the coils 25 is taken from a suitable supply disposed passage l5 leading ‘from the reservoir. A suitable valve I1 is disposed in the passage ii to control the ?ow of liquid therethrough. The 40 and in the form disclosed is actuated by a piston on its upper or lower side depending on whether it is desired to open or close the valve i1. 0b 45 viously any other valve controlling device may be used as it is well known in the art to substitute a liquid controlling means for the pneumatic means disclosed. It has been found in practice that as the pres 50 sure pad 5 descends and the piston 9 forces oil out of the cylinder ll , the oil shows a marked rise in temperature due to the friction which it en counters in passing restricted. parts of the pas sage around the valve II. In use, it is desirable to lock the pressure pad in its lowered position by As shown in Fig. 4, the cooling medium for“) main 3| through an intake pipe 33 having a valve 1 35 disposed therein. The pipe 33 .is‘connected to each of the coils through branches 3‘! and 39, terminating in respective unions 21, and ,each *5 controlled by a suitable valve 40. At the opposite end the coils are‘ connected to discharge pipes 42 and 44 which join in a main discharge pipe 46 connected to a sewer or other outlet“. It will thus be seen that the quantity of cooling 50 medium circulated through the coils may be reg~ ulated to control the working temperature of the liquid used in the hydraulic cushion. If it is desired to lower the temperature slightly, the valve 35 may be opened to permit a slow circula- 66 2,113,311 2 \ spaced interconnected cooling means in the re tion of the cooling medium, while it it is desired ceiver in the path of ?uid forced through the to lower the temperature of the cushioning liquid transverse passage, each of said interconnected to a greater extent, the valve 3'5 may be opened cooling means having a portion thereof in aline to permit a greater circulation of ‘the cooling ment with the uninterrupted passage, and means medium. - . connected to the cooling means for controlling While the invention has been described in con the latter. nection with a particular type of hydraulic cush 2. In a press of the character described having ion, it should be expressly understood that it is a cushion pad and a piston carried by said pad, capable of use with any other known type of 9. cylinder formed to receive said piston and hav cushioning means which employs a liquidhaving ing an uninterrupted ‘transverse passage at its 10 a tendency to become hot in use. Obviously, nu merous changes in the form and disposition of the coils may be made without departing from the invention as de?ned in .the appended claims. 15 What I claim is: ‘_ a 1. In a press of the character described hav ing a,v cushion pad and a piston carried by said pad, a cylinder formed to receive said piston and » having an uninterrupted transverse passage at 20 its lower end, a ?uid containing receiver asso ciated with the cylinder and having communi cation with the latter through said transverse passage, means for forcing ?uid from the receiver into the cylinder to actuate the piston, a pair of lower end, a ?uid containing receiver associated with the cylinder and having communication ~with the latter through said transverse passage, means for forcing ?uid from the receiver into the cylinder to actuate the piston, a pair of spaced longitudinally extending ‘interconnected cooling coils in' the receiver in the path of ?uid forced through the transverse passage, each of said in terconnected cooling coils having a portion there—. of in alinement with the uninterrupted passage, and means connected to the cooling coils for con trolling the latter. , . FREDRICH J. RODE.