US1713974A

US1713974A - Forging press or like machine

Info

Publication number: US1713974A
Application number: US697405A
Authority: US
Inventors: Massey Harold Fletcher
Original assignee: Individual
Current assignee: Individual
Priority date: 1923-03-09
Filing date: 1924-03-06
Publication date: 1929-05-21
Anticipated expiration: 1946-05-21

Description

May 21, 1929.

H. F. MASSEY FORGING PRESS OR LIKE MACHINE Filed March 6, 1924 til. 1

5 Sheets-Sheet l y 1, 1929. H. F. MASSEY 1,113,974

FORGING PRESS OR LIKE MACHINE Filed March 6, 1924 5 sheets-sheet 2 P Q ll/d May 21, 1929. H, F MASSEY 1,713,974

FORGING PRESS OR LIKE MACHINE May 21, 1929. I H. F. MASSEY .9

FORGING PRESS OR LIKE MACHINE Filed March 6, 1924 5 Sheets-Sheet 4 WIIILQIIII/l/ ama H. F. MASSEY May 21, 1929.

FORGING PRESS OR LIKE MACHINE Filed March 6, 1924 5 Sheets-Sheet 5 Patented May 21, 1929.

HAROLD FLETCHER MASSEY, OF DISLEY, ENGLAND.

' FORGING PRESS OR LIKE MACHINE.

Application filed March 6, 1924, Serial. No. 697,405, and in Great Britain March 9, 1923;

The invention relates to power presses and machines of the kind in which power is transmitted from a revolving crankor eccentric through a hydraulic cylinder or cylinders with one piston or more therein to the press head which is thereby caused to reciprocate.

The invention has for its principal object to improve the control and adj ustability of such presses and machines and thus to make them better adapted for various classes of work such as forging, upsetting, embossing, swaging, punching, cutting.

WVith this principal object the invention consists in a power press having improved controlling means for effecting the variation or adjustment of the position of reciprocation of the head operating on the work and in which reciprocating motion is transmitted from a revolving crank or eccentric through liquid in pressure spaces and the position of reciprocation is varied or adjusted by the use of controlling means, comprising a valve or valves with relative ports, preventing when in a neutral position or closed position flow of liquid to and from one pressure space to and from another opposed thereto or a reservoir or both and capable of movement from the neutral position in either of two directions so as to permit such flow in one direction only at a time in order to adjust the head in one direction or the other and mechanism provided for the operation of the controlling means is contrived so that the adjustment of the head restores or tends to restore the neutral position.

The invention consists further in presses of advantageous construction having such controlling means.

The connexion between the crank or eccentric and the head of a press hydraulic commonly by water or oil and as oil is usually employed this only will be referred to in further description and for simplicity the word press will be used instead press or machine, and crank will be used instead of crank or eccentric and also the head will be assumed unless otherwise stated to work in a vertical position above the work although it may operate in a horizontal or inclined po sition or may be vertical below the work.

. Some methods of carrying this invention into effect are shown by way of example in the accompanying drawings in which Fig. 1

is apartial front elevation and Fig. 2 is a vertical section taken on the plane indicated by the

line

2, 2 of Fig. 1 with some parts shown in side elevation for clearness showing one form of power acting cylinder. Figs. 1y vertical sections on by the lines 33 and part of a power press generally similar to that shown in Figs. 1 and 2 but with valves of different form. 5 is a horizontal section taken on the plane indicated by the lines 55 of Figs. 3 and 4 but drawn upon a larger scale and showing parts in plan for clearness. Fig. 6 is a side elevation partly in vertical sections on the plane indicated by the line 66 of Fig. 7 showing apower press with two stationary cylinders and Fig. 7 is a horizontal section taken on the plane indicated by the line 77 of Fig. 6. Fig. 8 is a side elevation in part a vertical section showing a power press similar in many respects to that shown in Figs. 1 and 2 but with the cylinder made to work horizontally.

The same numerals of reference are employed to indicate corresponding parts in different figures.

In the power press shown in Figs. 1 and 2 in which a head 11 comprising a double acting cylinder 12 works between vertical guides 13 in a frame 1 1, the frame 14 formed of two castings bolted together side by side carries a crank shaft 15 revolved in bearings 16 by power in any suitable manner as, in the case shown, by means of a belt pulley 17 serving also as a fly wheel.

The crank shaft 15 is normally kept revolving but may be started and stopped as desired. The speed of revolution is generally constant but provision may be made for it to be varied if desired.

A crank or eccentric 18 on the crank shaft press having a double 3 and 4 are respectivethe planes indicated 15 by means of the connecting r0d19 gives across head 20 a reciprocating up and down movement between the slides 21 formed in the frame 14. Attached to the cross head 20 is a piston rod 22 which extends downwards carrying a piston 23 furnished with a hydraulic cup leather packing 24: working in the cylinder 12 formed in the head 11 and provided at the top with a cover 25 presenting a hole through which the piston rod 22 can slide.

4.4 of Fig. 5 showing,

iii

The head 11 carries a pallet 26 which works in co-operation with a lower pallet 27 carried on the frame 14.

The head 11 is connected by means of chains 23 passing over

pulleys

29, and 31 to the balance weight 32 which is of the same weight as the head 11. The sides of the head 11 are made to extend up above the top of the cylinder 12 so as to form a reservoir with a cover 34 with a stuliing box 35 through which works the piston rod 22. The reservoir made to encircle the piston rod 22 in order that the oil in the reservoir shall prevent air from passing into the cylinder 12. In the head His formeda valve chamber 36 communicating with the reservoir 33 at the top directly and at the bottom by a passage 37. Ports'38, 39 connect the valve chamber 36 with the cylinder 12 at the ends respec tively above and below the piston 23.

In the valve chamber 36 works a valve 40 which is provided with

pistons

41, 42 for closing the

ports

38, 39 respectively and with one way valves 43 44 opening towards one another provided in

tli pistons

41, 42. The valve 40 is shown in its neutral or closed position in which the

pistons

41, 42 close the

ports

38, 39. Above the piston 41 the valve 40 is provided with openings 45 placing a central cavity 46 in the valve 40 in communication with the'reservoir 33. The upper portion of the valve 40 which works through an opening in the cover 34 is attached by a joint to a lever 47 the other end of which is connected by arod 48 to an arm 49 which is fast upon a shaft 50 provided with a foot lever 51. The foot lever '51 is ordinarily held in a raised position by the spring 52 connected with the foot lever 51. The lever 47 at a point near its middle is connected by a connecting rod 53 to a more or less similar lever 54 placed above it. One end of the lever 54 is attached by means of a joint to the crosshead 20 and the other end is attached by means of a connecting rod 55 to a stationary point on the frame 14 namely, in the case shown to astud carrying the pulley 31. The head 11 is also formed with another passage 56 leading from the bottom of the cylinder 12 to the reservoir 33 and ordinarily closed at its upper end by a spring loaded relief valve 57, loaded so that it will remain closed unless a pressure beyond the maximum desired is attained in the lower part of the cylinder 12 in which case oil will flow from the bottom of the cylinder 12 to the reservoir 33. A relief valve 58 is also provided to open. downwards from the reservoir 33 to the part of the cylinder 12 above the piston 23 so that when oil opens the relief valve 57 some may pass into the top of the cylinder 12. In the operation of the machine the revolving crank or eccentrio 18 gives a reciprocating motion to the piston 23 and while the valve 40 is in the neutral position, as shown the oscillating motion will be communicated to the head 11 and balance Weight 32 and the same oscillating motion will be given to the valve 40 by means of the

levers

54, 47 and connecting rod 53. If now the foot lever 51 be depressed, a little the valve 40 will be lowered in the valve chamber 36 and this will open free COlllIIlUlllCt'L-tlOll through the port 38 between the top of the cylinder 12 and the reservoir 33 and will also allow oil to pass from the reservoir 33 to the bottom of the cylinder 12 through the

oneway valves

43 and 44. Then on the upstroke of the piston 23 tlie reciprocating motion of the head 11 will be interrupted and the head 11 will standstill or move less than the pis ton 23, oil being drawn from the reservoir 33 through the one-

way valves

43 and 44 into the bottom of the cylinder 12 and oil being expelled from the top of the cylinder 12 through the port 38 and the upper part of the valve 40 into the reservoir 33. On the downstroke of-the piston 23 however the one-

way valves

43, 44 will prevent oil from flowing out of the bot-tom of the cylinder 12 and the head 11 will therefore have the same down ward motion as the piston 23 but in a lower position than before. The head 11 is thus adjusted downwards but in the downward adjustment the ports 38, 39' will; again come opposite the

pistons

41, 42 and the valve 40 will be restored again to the neutral or closed position. The reciprocating motion will then continue but in a lower position than before. Further movement of the valve 40 downwards will cause a further downward adjustment of the position of the reciprocating movement.

If contrariwise after a downward adjustment of the head 11 the foot lever 51 be allowed to rise under the influence of the spring 52 the valve 40 will be raised and will open free communication between the bottom of the cylinder and the reservoir 33 through the port 39 and passage 37. It will also allow oil to pass from the reservoir 33 into the top of the cylinder through the one

way valves

43 and 44 but not to pass out. The position of the head 11 will thus be adjusted upwards until the upward adjustment has caused the

ports

33, 39 again to be closed by the

pistons

41, 42. It will be seen therefore that the head 11 while in effect continuing its reciyn'ocatil'ig movement follows the movement of the foot lever 51 both up and down. If in any downstroke of the head 11 the ie sistance offered to the pallet 26 should be so great that a pressure higher than a predetermined maximum is produced in the bottom ofthe cylinder 12 the relief valve 57 will allow oil to pass-from the bottom of the cylinder 12' into the reservoir 33 in the con tinued downward moven'imm of the piston 23 while the relief valve 58 will allow oil to flow from the reservoir 33 into the top of the cylinder 12 and the head 11 will thus be allowed to remain stationary while the piston 23 descends. ii hile the piston 23 descends rela tivelyto the head 11 the cross head 20, levers 54, 47 and connected rod 53 will move the valve 40 downwards relatively to the

ports

38, 39 and therefore unless the foot lever 51 be allowed to rise, the head 11 will eventually be restored to the adjustment relatively to the piston 23 which obtained before the pallet 26 cncoimtered the excessive resistance. The oil in the reservoir 33 surrounding the piston rod. 22 and extending above the opening of the valve 57 prevents air from passing into the cylinder 12.

Figs. 3, 4 and 5 show an alternative arrangement of valve applied to a head ll suit' able for use in a frame 14 and with other parts as shown in Figs. 1 and 2. It will be seen that the

ports

38, 39 in the head 11 are generally as shown in Figs. 1 and 2, but that there are'two

horizontal valves

59, 60 made to turn in cavities in the head 11 instead of the one vertical piston valve 40. Each of these

horizontal valves

59, 60 is in the form of a short tube closed at each end. At the rear end levers 61, 62 are attached to the valves 59,

. 60 and are connected by the connecting rod 63 and can be moved up and rocking lever 47 shown in Figs. 1 and 2. In the sides of each

valve

59, 60 there are ports as shown where required to correspond with the

ports

38, 39 in the head 11.. There is also' a diaphragm 64 across the middle of each tube dividing it into two chambers a back chamber and a front chamber. In the diaphragm 64 there is a one way valve 65 which allows oil to flow from the back chamber to the front chamber but not in the reverse direction. The cavities in which the

valves

59, 60 are mounted are made to communicate, the upper by a short passage with the reservoir 33 and the lower by the passage 37 also'with the reservoir 33. The

valves

59, 60 are shown in the neutral position, the

ports

38, 39 being blocked andshut off from both the front and the back chambers, and the flow of oil between the top and the bottom of the cylinder 12 and between the cylinder 12 and the reservoir 33 being thus closed. It the connecting rod 63 attached to the rocking lever 47 be now raised by the foot lever being raised the valves 59, to will turn in. the head 11 clockwise in Figs. 3 and 4 and the port 38 will be opened to the front chamber of the valve 59 and the port 39 will be opened to the back chamber of the valve 60 and oil will be allowed to flow into the top of the cylinder 12 from the reservoir 33 and out of the bottomof the cylinder 12 into the reservoir 33 on the downstroke of the piston 23 but not to flow in reverse directions in the upstroke. The head 11 will thus be adjusted upwards as .in the construction shown in Figs. 1 and 2 and in moving up the head 11 will move relatively to the rocking le vcr 47 so that it will restore or tend to restore the

valves

59, 60 to the neutral position. If the connectingrod 63 be moved downwards down by the

valves

59, 60 is just the same as with the vertical valve 40 described with reference to Figs.

'1 and 2.

In .the power press shown in Figs. 6 and 7 two double acting

stationary cylinders

78, 79 formed in a casting are used containing re,- spectively the pump piston 80 and the press piston 81 connected with the head. The piston 80 is connected by the piston rod '82, .crosshead 83 and connecting rod 84 with the crank 18 on the crank shaft 15 and the piston 81 is connected by a pistonrod 85 with the head 86 that carries the pallet 26.

Stufling boxes

87, 88 are provided around the

piston rods

82, 85 respectively. Slides are provided in the frame 14 of the press to guide the head 86 and cross head 83 and hydraulic cup leather packings 89, 90 are provided in the pistons 80, 81 respectively. The upper ends of the two cylinders 7 8, 7 9 are connected by a passage 91 and the bottoms of the two

cylinders

78, 79 are connected by a passage 92 and the

passages

91, 92 are formed so as always to allow free communication between the connected ends of the two cylinders 78.79 al though a tube 93 forming the valve chamber 94 extends across such passages 91. 92. The connected parts of the two cylinders 78. 79 and the

passages

91, 92 connecting them thus form two opposed pressure spaces. The reservoir 33 for oil is connected by a passage to the lower end of the valve chamber 94. The reservoir 33 is made to extend above the upper opening of the valve chamber 94 and the opening of the valve 57 so that as in the press shown in Figs. 1 and 2 the oil in the reservoir 33 prevents air from passing into the

cylinders

79, and 80. An opening closed by the relief valve 57 is provided in connexion with the passage 91 and the passage 92 is provided with a one way valve 58 for the inlet of oil from the reservoir 33 through the passage. A hole is formed in the casting between the

cylinders

78, 79 for the insertion of and access to the one way valve 58 and the cover 95 screwed in the casting and forming the abutment for the spring used with such valve 58.

A piston valve 96 in the valve chamber 94 is provided to fulfill the same functions as the piston valve 40 shown in Figs. 1 and 2 being provided with

pistons

97, 98 to close openings in the valve chamber 94 in connexion with the

passages

92, 91.'respectively and with a central cavity 99 with inwardly opening oneway valves 100. 101 at each end. In principle the action of the valve 96 is precisely similar to that of the valve 40 shown in Figs. 1 and 2. but in the case of Fig. 6 the cylinder 7 9 is' stationary and consequently it is nec-- essary that the automatic movement resulting from the adjustment ofthe .head 86 by means of the foot lever 51 shall be communicated to the valve 96 itself, instead of, as in Figs. 1 and 2, to the valve chamber 94. In order that this automatic movement may be communicated to the valve 96 a lever 102 in connexion by the rod 103 with the valve 96 and by the rod 104 with the foot lever 51 is mounted to oscillateabout a pin or stud 105 in connexion by a link 106 with approximately the middle of a lever 107 in connexion at one en d by a pin with the head 86 ot' the press and engaged by a rounded part with a cavity 108 in the cross head 83, the rounded end and the cavity 108 being formed to allow oscillation and lengthwise movement of the lever 107. It is clear that as the pump piston 80 moves up and down the head 86 must move down and up, the lever 107 will therefore have a rocking motion. and the centre or some other point between the ends will remain approximately stationary so far as the reciprocating motion is concerned. It will however move up and down as the adjustment of the head 86 takes place. The link 106 therefore attached at this point. It the foot lever 51 is depressed the valve 98 is raised from its neutral position and opens the

ports

91, 92 so that oil is allowed to flow into the pressure space above the pistons 80, 81 and out of the pressure space below the pis tons 80. 81 and causes the posit-ion of reciprocation of the head 86 to be adjusted downwards and the downward adjustment causes the pivot of the link 106 to be lowered with r the effect that the valve 96 is lowered again and brought back to its neutral or closed po sition. A similar action takes place in the reverse direction if the foot lever 51 be allowed to rise.

The position of the reciprocation of the head 86 therefore follows the movement of afoot lever 51 exactly as in the case of the 'presses described with reference to Figs. 1,

2, 3 and 4;.

Vertical presses have thus far generally been described in which the downstroke is the working stroke. It will readily be understood that a press might be contrived for the rain to work in any other direction such changes involving no alteration other than rte-arrangement or omission of the means needed for balancing or returning the head of the press in the direction contrary to that of its working stroke or the re-arrangen'ient of the reservoir and other parts to suit the changed position. For example Fig. 8 shows a press similar to that illustrated in Figs. 1 and 2 but contrived or disposed for the head 11 to work in a horizontal direction and without a balance Weight 32 which in this case is unnecessary since the weight of the head 11 of the press has no influence tending to move it in either of the directions in which it is intended to work. Fig. 8 shows the reservoir 33 at the end of the cylinder and encircling the piston rod 22 and made to extend upwards above the opening of the valve 57 and so as in the case of the press shown in Figs. 1 and 2 the oil prevents air from passing into the cylinder 12.

In order that the invention may be more completely understood the salient features will be indicated in the further description following.

The hydraulic connexion between the revolving crank or eccentric, whether constantly revolving or started and stopped as desired or whether the speed of revolution is C011- stant or provision is made for it to be varied as desired, and the head of the press may consist of one cylinder or more with one piston or plunger therein and the pressure is transmitted by means of liquid usually oil in pressure spaces thus formed.

Usually two pressure spaces are used the one to force the head in the forward direction and the other opposed thereto to force it in the reverse direction.

In a double acting cylinder or pair of double acting cylinders one end or pair of ends forms one pressure space and the other end or pair of ends forms another pressure space opposed to the first. Such a pair of cylinders may be at any convenient distance apart and joined in any suitable way.

. The relation between the strokes of two cooperating pistons or plungers will depend upon their relative diameters.

"Whether each pressure space consists of one cylinder end or two connected cylinder ends, the head will reciprocate in harmony with the crank, but the position of reciprocation will be varied if the amount of liquid in one or other of two opposed pressure spaces is increased or diminished.

For eiiecting the variation or adjustment of the position of reciprocation of the head means are provided which comprise controlling means consisting of a valve or valves with relative ports which in its neutral or closed position prevents flow of liquid to and from one pressure space from and to another opposed thereto or a reservoir or both and which is capable of movement from the neutral position in either of two directions so as to permit such flow in one direction only at a time in order to adjust the head in one direction or the other and operating mechanism contrived so that adjustment of the head restores or tends to restore the neutral position.

A controlling means such as a valve or valves is or are provided to regulate the flow of liquid between the opposed pressure spaces. In the neutral or normal position of the controlling means flow of liquid from one pressure space to the other is prevented. If however the controlling means he moved from this neutral position in either direction, flow of liquid is permitted from one pressure space to the other but not in the reverse direotion, with the result that the head will follow the movement of the crank or eccentric in one direction but not in the other, and thus the position of reciprocation of the head will be changed or adjusted. Movement of the controlling means in the other direction from the neutral position will cause the head to be adjusted in the reverse direction.

If the capacity of one pressure space is larger than that of the other, a reservoir is used to supplement the capacity of the smaller pressure space and when only a single pressure space is used such reservoir is used instead of a second pressure space.

In order that the control of the position of reciprocation of the head maybe easy, the mechanism for operating the controlling means is so contrived that, as the position of reciprocation of the head changes in adjustment brought about by a movement of the controlling means from the neutral position, the adjustment restores or tends to restore the controlling means to the neutral position. This causes the adjustment of the head auto matically to cease and the head to continue reciprocation in the position to which it has been adjusted.

In order to prevent excessive pressure from being attained a relief valve is used in connexion with the pressure space for producing the forward stroke. This relief valve is loaded for example by a spring so that in case of a pressure higher than the predetermined amount being attained liquid will pass out of this pressure space. i

In cases in which the head works in other than a horizontal position it may be balanced, for example by a balance weight.

What I do claim as my invention and deside to secure by Letters Patent is:

1. A power press comprising a head adapted to receive reciprocating motion, an eccentric part adapted to revolve for transmitting reciprocating motion to said head, two pres sure chambers containing columns of liquid,

means presenting pressure faces in said pressure chambers respectively and in connexion with said eccentric part to be recipro'cated thereby and according to the direction of movement to apply or to receive pressure to and from said columns of liquid, means presenting pressure faces in said pressure chambers respectively and in connexion with said head for enabling said head to receive and to to the other and to said apply pressure from and to the columns of liquid in said chambers, a reservoir, passages for-connecting said pressure chambers each reservoir, valvular controlling means for controlling said passages having a neutral position in which flow of liquid between the pressure chambers and the reservoir is prevented and manually movable in either of two directions from the neutral position to allow flow in one direction only at a time from or to one or other pressure chamber and the reservoir for adjusting the position of reciprocation of the head and means connecting the head and the valvular means whereby the adjustment consequent upon the movement of the valvular controlling means restores such valvular controlling means to its neutral'position.

2. A press according to claim 1', characterized by a relief valve allowing liquid to es cape from one of when more than a attained.

ized

predetermined pressure is by a moving head containing the pressure chambers.

ed in said head comprising a piston valve and co-operating oppositely opening one-way the pressure chambers press according to claim 1, charactervalves. 7

8. A press according to claim 1, character ized by a moving head containing the pressure chambers and a relief valve allowing liquid to escape from one of the pressure chambers when more than a predetermined pressure is attained.

In testimony, that I claim the foregoing as my invention, I have signed my name this fifteenth day of February, 1924.

HAROLD FLETCHER MASSEY.

ioo