Патент USA US2108746код для вставки
Feb. 15, 1938. A. M. ERICHSEN 2,108,745 SAFETY DEVICE FOR MACHINE PARTS SUBJECT TO HIGHIPRESSURES Filed Jan. 27, 1937 $11M 4 ' W / /// iii 22’/////// _ VIII/K f , , 2 Sheets-Sheet 1 i / . gin/W1 Feb. 15, 1938. A, M_ ERICHSEN 2,108,746 SAFETY DEVICE FOR MACHINE PARTS SUBJECT TO HIGH PRESSURES Filed Jan. 27, 1937 Ffg .5. / , . 2 Sheets-Sheet 2 3 %// I, I W .*l Q/ 2 \ E \H v 29 3 / XW \\\~ 1 L 33 / 2 //7 Mental‘: GXMLW mm MM 5 mwmw 2,108,746 Patented ‘Feb. is, 1938 UNITED STATES ‘PATENT OFFICE r 2,108,748 SAFETY DEVICE FOR moms rAa'rs sua mo'r T0 men rnassuaas - Abraham Martinius Erichsen,‘ Teltow, near Ber lin, Germany Application January 27. 1931, Serial No. 122,532 In Germany March 24, 1934 -9 Claims. (CI. 80-57) The invention relates to safety devices for the relief or adjustment or reduction of the pressure on‘ machines and machine parts of every kind working with high pressures, such as rolling mills, presses and the like, in which the pressure medi-» um of an hydraulic apparatus acts upon a safety member which at a predetermined pressure limit permits the escape of the pressure medium. - Hitherto such apparatus has required a liquid 10 pressure medium and has necessitated packing which, under the high pressures at which the safety device is to act, has been such as to arrest or delay the action of the safety device. This disadvantage is overcome according to the 15 invention by utilizing a non-liquid pressure me dium, that is, one which only ?ows under’ con siderable pressure. Rubber, rubber dough, plas ticine, gelatine or other like elastic or plastic non liquid masses are suitable for this purpose. 20 The use of such a pressure medium, which is self sealing, dispenses with the necessity for pack ing devices, such as hitherto employed, which under the pressures in question frequently fall. A more certain functioning of the safety device 25 is assured at a determined pressure limit. The pressure is taken up by the mass, with the simul taneous production of a secure and reliable pack ing and transferred or distributed to the safety element which, on attainment of the determined 30 pressure limit, comes into action and causes Figures 1 and 2 are, respectively, a sectional elevation and a plan view of one form of the invention in which the automatic device in the form of a shearing disc and the hand regulated device are arranged separately. Figure 3 is a side elevation, partly in section, of another form in which the automatic device and the hand regulated device are combined. Figure 4 shows the application of the inven tion to a rolling mill spindle. Figures 5 and 6 are, respectively, a sectional elevation and a plan view of a further form of 16 the invention. Figure '7 is a sectional elevation of a form of the invention in which two different non-liquid masses are used, one serving as ejection mate rial and the other as packing material. In the form of the invention shown in Figure 20 l, i is the housing of the pressure chamber con taining the pressure medium 2, which acts on the safety device under the pressure of a piston 3, on which, for example, the pressure of a rolling mill spindle 4 (Figure 4) acts. The pressure 25 chamber in the example illustrated consists of an upper part5 and a lower duct 6, which are connected by one or more openings or ducts ‘I. In, Figures 1 and 2, one end of the duct 6 is pro vided with a shearing'disc 8 which is arranged the pressure mass to flow from the pressure cham between the chamber wall and a nipple 9, which ber, in which the pressure is thereby wholly or is screwed into the latter and on removal permits partially relieved. ‘ ‘ When the machine jams owing to anundue 35 increase in pressure, for instance, when a rolling mill is blocked and the billet which is being rolled jams, according to the invention, the pres sure can be relieved, without further ado, by hand, by means of a hand operated device which 4:0 allows some'of the mass to escape from the pres sure chamber so that the pressure is reduced to the desired degree. After the pressure has some what relaxed in this manner, the usual starting devices for the rolls may be operated again so 45 that the pressure is wholly relieved. The safety and relieving means may also be combined in one device, the former operating automatically on a determined pressure being reached, and the other being regulated by hand. The mass used as pressure medium may serve at the same time to measure the pressures occur ring, some of the medium being forced out through one or more openings in the pressure 55 of the invention‘ are illustrated by way of ex ample:— chamber, or acting upon a member introduced from the outside, so that the amount of the ma terial pressed out, or the extent of the ejection movement of the introduced body, is indicated by a gauge or the like. In the accompanying drawings, several forms of renewal of the disc. According to the invention, a pressure trans mitting medium consisting of a non-liquid mass 35 2, such as rubber, synthetic or plasticized rubber, plasticine and the like, as pressure transmitting medium, is acted upon by the pressure piston 3 in the pressure chamber and also acts as a se cure and reliable packing for the piston under 40 all pressures which occur. By means of the mass 2 of'rubber or the like, the pressure is uniformly taken up and transmitted to the safety element 8, so that the latter comes into action at the predetermined highest pressure, thus avoiding 45 the use of the usual packings which are frequent 1y unreliable in action, render the arrangement expensive and complicated, and often require repair. In the form of the invention illustrated 50 in Figures 1 and 2, the whole pressure chamber is ?lled with rubber or the like, which acts on the safety member 8 and is capable of ?owing when the determined pressure limit at which the safety member comes into operation is reached, or pos 55 sibly- somewhat earlier. The pressure acting on the piston 3 is taken up uniformly by the mass 2 and spreads within the mass, so that on a rise of pressure over a‘ certain limit the shearing disc is pressed out by the mass 2. The mass 2 which 60 2 passes over into the ?uid condition can now es cape from the pressure chamber so that the pres ward displacement of the regulating plunger or the like,,an increase .in pressure and displacement sure in the latter, and thereby also in the machine of the pressure plunger 2, Figure 1, can be e?ected ‘ concerned, is relieved or reduced. If a large and of the machine part or the like resting on it, proportion of the mass flows out, the chamber _ or of a machine part in?uenced by its setting. must be ?lled anew which can be e?ected in a In the form of the apparatus illustrated by short time. Figures 5 and’6, the pressure medium 2' which The device itself, apart from the shearing mem escapes from the pressure chamber I is auto _10 ber 8, which must be renewed, is not damaged or rendered unemployable' by the operation de scribed. . Besides theshearing device described, there is provided in Figures ,1 and 2, moreover, a device capable of being regulated by hand, which, for 15 example, is provided at the other end of the duct 6 and is used when the pressure is to be freed or relieved by hand. This device consists, for ex ample, of a screwed valve M which is mounted in a housing, II and is operated by means of "a 20 hand wheel or key applied to the squared end l2. By opening the valve ill, the pressure on the mass 2 can be so far relieved that the main pressure is relaxed. ' A pressure gauge l3, Figure 2, is provided for 25 indicating the pressure of the pressure medium and is actuated, for example, by some of the mass 2 being ejected through an opening of the pres sure chamber and acting through an intermediate 30 member on the indicating device. Instead of this, a member may also project into the pressure chamber and be pushed by the pressure of the mass 2 outwards in order to act on the gauge I3. In the form according to Figure 3 of the draw ings, the automatic device and the hand operated 35 device are combined. matically 'returned thereto until the plunger I regains its original position. v In this form or the appartus, the plunger I 10 slides on a screw 28, which limits its upward stroke. A sliding member in the form of. a valve _ I 20 having .a stem or plunger 2| is mounted vin ,a housing l9 which is provided with a gland 22. A 15 secondary chamber such as a- cylinder 24 is screwed .onto the housing l8 and- secures the gland 22. The secondary chamber 24 contains a pressure medium such‘ as a plastic or resilient mass 23 and with means for regulating the initial 20 pressure of this medium, for example, an adjust able screwed plug 25. The‘stem or plunger 2| enters the chamber 24. A duct 21 connects the housing I! with a re ceiver 28, which is also connected by means of a 25 return duct 29 to the pressure chamber I. The duct 29 is provided with a valve box 30 contain ing an automatic check valve such as a ballvalve The receiver 28 is adapted to be variable in 30 volume automatically, that is to say, it is ex pansible and contractible, for instance, it may be formed of resilient or elastic material, as shown, or it may be a rigid vessel ?tted with a plunger or piston loaded by a weight or spring. The pressure ' In this form, a sleeve 35 is screwed at 36 into chamber |, the ducts 21 and 29 and the vessel the wall of the chamber | and contains an auto 28 are ?lled initially with pressure medium. The matic relief valve l5 which is loaded by a spring _ pressure at which the medium 2 is to open the M, the tension of which can be regulated by a 40 plug I6 having a portion 38 screwed into the in valve 20 automatically is determined by screwing in the plug 25 to regulate the pressure of the 40 medium 23 in the chamber 24. When the valve 20 opens, due to an undue pres receive a key 4| provided with a squared bore 40 I sure on the plunger 3, the medium 2 escaping and with a hand wheel IT. The key 4| abuts from the chamber l enters the duct 21 and the 45 against a cap 42 formed on the part 38 and adapted to slide over the adjacent part of the pressure is transmitted to that in the vessel 28, 45 which'expands as indicated by the dotted lines sleeve 35. It has a scale on its edge l8 to indi 28’. When' the undue pressure on the machine cate the amount of displacement. ' part is relieved, the valve 20 closes, the chamber By the above means, the predetermined pres 28 contracts and a corresponding amount of 50 sure at which the valve | 5 is to operate to allow pressure medium 2 to escape can be regulated by pressure medium is returned by the duct 28 past 50 setting the tension of the spring l4 by means of the valve 3| to the pressure chamber |. The plunger 3 is returned to its normal position de the hand wheel l1, and,‘ if desired, immediate re termined by the screw 26. lease of the pressure medium may be effected by Hand release of the valve 20 can be e?ected at 55 rotating the hand wheel I‘! to relieve the tension of the spring l4. The form of apparatus shown any time required by screwing back the plug 25. 55 The elastic pocket 28 may be replaced by a in Figure 3 may be provided with a pressure similarly acting device, for example, by a plunger gauge similar to that shown in Figure 2. The mass 2 in the pressure chamber in the which is under spring pressure, the pressure of 60 forms of apparatus above described may be‘ which is so strong that the mass 2 ?ows back placed under a certain adjustable initial tension automatically into the pressure chamber until 60 by a pressure pin or plunger or the like capable of the plunger 3 takes up its original position. A plastic mass is in general to be preferred to being screwed from the outside into the pressure an elastic mass, for the pressure medium 2, since chamber. ternally screw-thread part 31 of the sleeve 35. The outer end of the part 38 is squared at 39 to 65 The shearing element 8, Figure 1, and the valves In, Figure 1, and I5, Figure 3, may also be replaced by equivalent means, for example, by a displaceable piston, slide or the like. Instead of permitting the pressure medium to 70 escape, which requires that it be renewed, the means, such as a regulating plunger, slide or the like, may be adapted in such a manner that by the receding of the plunger, the volume or the chamber is increased, whereby the pressure is 75 reduced or relieved. On the other hand, by in it is more di?icult to cause an elastic mass to ?ow. Both, however, can be used in combination, for 65 example, .as is illustrated in Figure 7, wherein 2 indicates the plastic mass which is to ?ow, whilst a highly elastic mass 32, for example, highly vul canized India rubber, is used for packing for the pressure piston 3. ' The mass 32 in this case only 70 has to be compressed and can always return again into its original form. The highly elastic mass 32 may bein the form of a packing ring of any suitable shape. Preferably, a conical packing ring 3 2,108,746 33 of metal or‘ the like may be inserted at the packing joint. ' mined‘ maximum pressure is reached, comprising a pressure chamber, a pressure medium in said ' For increasing the tightness, the pressure chamber, said medium being a non-?uid homo geneous whole capable of ?owing at a pressure plunger 3 in all forms of construction may be pro vided at the edge of its face opposed to the pres _' not above said maximum pressure, a plunger for sure medium 2 with inner conically extending compressing said medium under the pressure ap or inwardly bent round projections, or may be plied to the aforesaid parts of the machine to be hollowed out on the underside. controlled, a safety relief valve on said pressure I claim: chamber, a secondary pressure chamber con 1. A safety device to be interposed between taining a non-?uid pressure medium capable of 10 parts of a-rolling mill, press or other like ma ?owing at a pressure at least as low as said max chine liable to be subjected to heavy pressure imum pressure, said valve having a stem protrud and adapted to relieve the pressure when a de ing in said secondary chamber and being sub termined maximum pressure is reached, compris 15 ing a pressure chamber having an escape ori?ce, a pressure medium‘ in said chamber, a plunger in said chamber for compressing said medium under the pressure applied to the aforesaid parts of the machine to be controlled, a safetyelement normally closing said escape ori?ce, said safety element being subjected to the action of the pres sure medium and adapted to open said ori?ce when the determined maximum pressure is reached, the said pressure medium being a non fluid homogeneous whole which is capable of ?ow ing at a pressure at least as low as said maximum pressure. . . ' - 2. A safety device as specified in claim 1, where in said pressure medium is partly composed of a non-?uid homogeneous whole capable of ?owing ject‘ed to the pressure of the medium therein, and hand operated means for regulating the pressure of the medium in said secondary chamber, an escape duct for the medium discharged by the relief valve from the main pressure chamber, an expansible receiver on said duct, a return duct from said receiver to the main pressure chamber and a check valve in said return duct. 6. A safety device to be interposed between parts of a rolling mill, press or other machine liable to be subjected to heavy pressure and adapt ed to relieve the pressure when a determined max imum pressure is reached, comprising a pressure ' chamber, a pressure medium in said chamber, said medium being a non-?uid homogeneous whole capable of ?owing under pressure, a plung er for compressing said medium under the pres 30 at a pressure at least as low as said maximum sure applied to the aforesaid parts of the machine pressure'and partly of a highly elastic material to be controlled, a loaded relief valve on said pres sure chamber for permitting the escape of pres sure medium, hand operated means for varying the load on said relief valve counteracting the 35 pressure of the medium acting on said valve, an located adjacent t9 the circumferential edge of the face of the plunger and the side of the pres sure chamber. ~ g -3. A safety device to be interposed between parts of ‘a rolling mill, press or other machine liable to be subjected to heavy pressure and adapted to relieve the pressure when a deter 40 minedv maximum pressure is reached, comprising -. a pressure chamber, a pressure medium in said chamber, said medium being a non-?uid homo geneous whole capable of ‘?owing at a pressure at least as low as said maximum pressure, a plunger for compressing said medium under the pressure applied to the aforesaid parts of the machine to be controlled, said pressure chamber having an automatic safety element for control ling‘the escape of pressure medium and also a hand operated relief valve. " 4. A safety device to be interposed between »_ parts of a rolling mill, press or other machine liable to- be subjected to heavy pressure and adapted to relieve the pressure when a deter 65 mined maximum pressure is reached, comprising a pressure chamber, a pressure medium in said chamber, said medium being a non-?uid homo geneous whole, capable of ?owing at a pressure expansible receiver for the medium discharged by said relief valve, a return duct from said re ceiver to the pressure chamber and a check valve in said return duct. . 40 7. A safety device as speci?ed in claim I, hav ing in the pressure chamber a pressure medium partly composed of a non-?uid homogeneous whole capable of flowing at a pressure at least as low as said maximum pressure and partly of a highly elastic material located adjacent to the circumferential edge of the face of the plunger and the side of the pressure chamber, and a me tallic packing between said plunger and said elastic material. 8. A safety device as speci?ed in claim 1 where in said pressure medium is composed of a plastic mass. 9. A safety device to be interposed between parts of a rolling mill, press or other machine liable to be subjected to heavy pressure and adapt ed‘ to relieve the pressure when a determined maximum pressure is reached, comprising a pres at least as low as said maximum pressure, a sure chamber, a pressure medium in said cham plunger for compressing said medium under the ber, said medium being a non-?uid homogeneous whole capable of ?owing at a pressure at least pressure applied to the aforesaid parts of the machine to be controlled, a safety relief valve as low as said maximum pressure, a plunger for on said chamber subjected to the pressure of‘ said compressing said medium under the pressure ap medium, resilient means for holding said valve plied to the aforesaid parts ofthe machine to be closed against said pressure until said maximum controlled, 9. safety relief valve provided with a pressureis reached, and hand operated means spring for holding it closed against the pressure for regulating said resilient means to determine in the pressure chamber, and hand operated the maximum pressure at which the valve is to means for varying the tension of the spring to open. determine the maximum pressure at which the .5. A safety device to be interposedbetween relief valve shall open to permit escape of pres 70 ‘parts of a rolling mill, press or other machine sure medium from the pressure chamber. liable to be subjected to heavy pressure and adapted to relieve the pressure when a deter ABRAHAM MARTINIUS ERICHBEN.