US2785535A

US2785535A - Fluid pressure-actuated apparatus

Info

Publication number: US2785535A
Application number: US370364A
Authority: US
Inventors: Jr Robert L Alcorn
Original assignee: Chambersburg Engineering Co
Current assignee: Chambersburg Engineering Co
Priority date: 1953-07-27
Filing date: 1953-07-27
Publication date: 1957-03-19
Anticipated expiration: 1974-03-19

Description

` March 19, 1957 R. L. ALcoRN, JR 2,785,535

FLUID PRESSURE-ACTUATED APPARATUS Filed July 27, 1955 3 Sheets-Sheet l www March 19, 1957 Filed July 27, 1953 R. L. ALCORN, JR

FLUID PRESSURE-ACTUATED APPARATUS '3 Sheets-Sheet 2 OR/FICE March 19, 1957 R. L. ALCORN, JR

FLUID PRESSURE-ACTUATED APPARATUS 3 Sheets-Sheet 3 Filed July 27, 1953 United States Patent O FLUID PRESSURE-ACTUATED APPARATUS Robert L. Alcorn, Sir., Chambersburg, Pa., assignor to Chambersburg Engineering Company, Chambersburg, Pa., a corporation of Pennsylvania Application July 27, 1953, Serial No. 370,364

7 Claims. (Cl. 60-97) This invention relates to fluid pressure-actuated devices in which there is at least one movable member that is moved through a work stroke and through a return stroke. An example of such a device is a forging apparatus in which a forging member is driven at high velocity against a work piece to be forged. One form of such apparatus that is now in use comprises two forging rams or impacters arranged horizontally in opposing relation to each other and which are operated very rapidly to forge successive work pieces that are fed to the apparatus. Such an apparatus is disclosed in U. S. Patent No. 2,615,306, issued October 28, 1952, to R. L. Alcorn, Jr., and assigned to the assignee of the present applica- Ition.

It is desirable to be able to move the work-performing member or members in such an apparatus slowly for inspection or checking, but it is usually impractical to move the work-performing member by hand. ln a double impacter apparatus such as above-mentioned7 for example, it is sometimes desired to check the dies for die setting, but this has been very difficult in the past due to difficulty in moving the impacters except in their usual high velocity operation.

One object of the present invention is to provide, in an apparatus of the general character above-mentioned, an arrangement whereby the Work-performing member or members can be moved slowly, i. e. inched or jogged, whenever desired to enable checking or inspection.

Another object of the invention is to provide such an apparatus which is easily operable by the operator, and which aifords complete safety to the operator.

A more speciic object of the invention is to provide such an arrangement in a double impacter forging apparatus of the character disclosed in the above-mentioned patent.

Other objects and features of the invention will be apparent from the following detailed description.

While the inveniton contemplates the provision of an inching or jogging arrangement in any apparatus of the general character above-mentioned, it will be described herein with specic reference to its embodiment in a double, impacter forging apparatus of the character disclosed in the above-mentioned patent, especially since a specific object of the invention is to provide inching or jogging control in that apparatus.

ln the accompanying drawings,

Fig. l is a front elevational view of a double impacter forging apparatus to which the present invention is applied;

Fig. 2 is a diagrammatic illustration of the control arrangement employed in the apparatus;

Fig. 3 is a detailed illustration of the control arrangement; and

Fig. 4 is a diagrammatic illustration of the electrical system employed.

Referring rst to Fig. 1, the illustrated apparatus comprises a supporting frame on which are mounted two horizontally aligned uid cylinders 11 and 11a within which there are movable rams or impacters 12 and 12a to which the forging dies 13 and 13a are removably attached. In the illustration the impacters and their dies are shown in their innermost positions Without a work piece interposed, the dies being in abutting relation to one another. rlhis is the condition of the movable parts for inspection when the apparatus is now in operation. lt will be understood that during forging operation of the apparatus the dies 1 3 and 13a engage a work piece to forge the same to a desired shape.

For the purpose of the present application, it is only necessary to give a general description of the apparatus preparatory to a description of the present invention. Referring still to Fig. 1, during forging operation of the apparatus pressurized lluid, which is preferably compressed air, is supplied to the outer ends of the cylinders to drive the rams or impacters through their Work stroke. Immediately following the forging of a work piece the rams or impacters are moved through their return stroke by admitting pressurized iluid to the inner ends of the cylinders, and at the same time the previously admitted duid is exhausted from the cylinders.

Figs. 2 and 3 show the fluid control system by which the rams or impacters are actuated. Fig. 2 is a generalzed illustration of the complete system, While Fig. 3 is a detailed illustration showing how each ram or impacter is actuated. Referring particularly to Fig. 3, the pressurized uid to operate the ram or impacter 12 through its work stroke is introduced to the pressure end of cylinder l1 from conduit 14 through chamber 15 and port 16 when valve 17 is open and valve 18 is closed. Pressurized uid to actuate the ram or impacter 12 through its return stroke is introduced through conduit i9 to the return end of the cylinder 11, and during the return stroke valve 17 is closed and valve 18 is open as shown, to exhaust the previously admitted fluid through exhaust port 2G. Valves 17 and 1S are actuated by pressurized fluid under control of a solenoid-operated valve 21. A second solenoid-operated valve 22 serves to control the admission of fluid pressure to the return end of cylinder 11, and also to control the exhaust of such fluid. The solenoids 23 and 2d for operating the

valves

21 and 22 are controlled by cyclic control apparatus represented in block form at 25, which apparatus may be of the character disclosed in Fig. 6 of the above-mentioned patent. Since the present invention is not concerned with the details of the cyclic control apparatus, there is no need to illustrate or describe the same. It suffices to note that this apparatus effects cyclic energization and deenergization of the solenoids as hereinafter mentioned.

The apparatus is shown `at the end of an operating cycle just prior to the opening of valve 17 and the closing of valve 18 to initiate a new operating cycle. Solenoid Z3 is deenergized, and under the influence of the biasing spring 26 the movable valve member 27 is in the position shown, and pressurized fluid is being supplied through conduit 2S, conduit 29, differential controlling valve 3d and conduit 3i to the pilot valve )i7 which is maintained closed by the applied pressurized huid. At the same time pressurized fluid is supplied through conduit 31a to the pilot valve of the other cylinder corresponding to the pilot valve 17. The differential controlling valve 30 cnables differential control of the fluid supply to the inlet pilot valves of the two cylinders, as described in the above-mentioned patent. Conduit 32, which connects with conduits 3? and 33a, is in communication with the exhaust conduit 3d of the valve 21 and, therefore, valve 118 and the corresponding valve of the other cylinder are open. Solenoid 24 is also deenergized, and movable valve member 3S is in the position shown under the inliuence of the biasing spring 36. Conduit 37, which connects with conduits 19 and 19a, is in communication With exhaust conduit 38.

Energization of solenoid 23 causes movement of valve member 27 to the right, placing conduit 32 in communication with the fluid supply conduit 28 and thus causes closure of valve 18 and the corresponding valve of the other cylinder. At the same time conduit 29 is placed in communication with exhaust conduit 39, causing opening of valve 17 and the corresponding valve of the other cylinder. At this time pressurized fluid is supplied to the cylinders to drive the impacters through their work stroke. At the end of the Work stroke solenoid 23 is deenergized and solenoid 24 is energized. The deenergiza ion :of ysolenoid Z3 causes closure of valve l7 and opening of valve i8, and correspondiny operation of the valves of the other cylinder. The energization of solenoid 24 causes valve member 35 to mov-e to the right, thereby placing conduit 37 in communication with uid supply conduit 4d. Pressurized fluid is then supplied to the cylinders through conduits 19 and 19a to drive the impacters through their return stroke. Solenoid Z4 is then deenergized and the movable elements are again positioned as shown in Fig. 3, for start of the next oper-ating cycle.

In order to cushion the impacters at the end of their return stroke, ran arrangement is provided at each cylinder as now to be described, and as wiil be seen later this same arrangement is conveniently used for the purpose of the present invention. Referring still to Fig, 3, it will be noted that the port i6 is located in spaced relation to the associated end of the cylinder l1, and a by-pass port 4l extends from the end of the cylinder and communicates with chamber l upon opening of a spring-biased valve 42 who-se biasing spring 43 ytends to maintain the Valve closed. At the end of the `return stroke of the impacter 11.2, some of the pressurized fluid is trapped at the lefthand end of the cylinder and serves to cushion the impacter. At the start of the neXt operating cycle, the operating fluid. entering from conduit i4 forces valve 42 open and enough duid is admitted through port 41 to move the impacter sufficiently to uncover the main port i6.

As thus far described, the apparatus is similar in structure and operation to that disclosed in the above-mentioned patent. 1n accordance with the present invention, an .arrangement now to be described is provided in association with each cylinder to enable inching or jogging movement of the impacters, and at the saine time prevent the apparatus from going through its cycle or forging operation.

As may be seen in Figs'. 2 and 3, solenoid-operated valves 44 and 44a are utilized to effect the inching or jogging operation. Referring particularly to Fig. 3, valve 44 is typical and is connected by conduit 45 to the chamber of valve 42 and thence to port 41. When the solenoid 46 is deenergized, the movable valve member 47 is in the position shown under the inuence of the biasing spring 48. In this position of the valve member 47, the inlet end of conduit 45 is closed. However, energization of solenoid 46 causes upward movement of valve member 47 to place conduit 45 in communication with a pressurized fluid supply conduit 49. This effects supply of pressurized fluid to the end of cylinder 11 through conduit 45 and port 41, but the quantity or volume of fluid flow is relatively low so as to exert relatively small force on the impacter 12 to move it slowly toward -the right. An orifice 50 is provided in conduit 45 to limit the volume of the fluid flow. The manner in which solenoid 46 is controlled will be described later.

As further shown in Figs. 2 and 3, the main fluid supply conduits l4 and 14a are connected `to spring-biased pressurenesponsive valves 51 and 51a. Valve 51 is typical, and as shown in Fig. 3 its movable valve member` is urged by the biasing sp-ring 52 into engagement with the valve seat. Conduits 53 and 53a connect the chambers of valves 5l and 51a with the chamber of a valve 54 through which the pressurized duid is supplied by conduit 55, the latter being connected to the pressurized duid source. The movable valve member 56 is pivotally CII connected to one end of a link 57 whose opposite end is pivotally connected to a manually-operable lever 58. The lever 58 has one end pivotally fulcrumed at 59 on a stationary bracket 60 mounted on the casing of valve 54. Lever 58 is weighted at 6l to urge the movable valve member 56 downward to the position shown. Link 57 has a recess or notch 62 therein which is engageable by the nose 63 of a latch element 64 pivoted at 65 on the valve casing. A tension spring 66 is interconnected between the latch element 64 and bracket 6&9 so as to urge the latch clement 64 to ineffective position. The latch element 64 is connected by a link 67 to the armature 68 of a solenoid 69, whereby energization of the solenoid 69 moves the latch element 64 to effective position and maintains it in that position. It will be seen, therefore, lthat if solenoid 69 is energized and if the lever 55 is manually raised, the movable valve member 56 is latched in raised position.

The lowered position Iof valve member 56, as shown, is the position for inching or jogging operation as hereinafter described. In this position of the valve member 56, 4the inlet port 7d of valve 54 is cut o from the outlet port 7l, so that the pressurized fluid supply .conduit 55 is effectively closed. At the same time the port 71 is in communication with an exhaust port 72. The pu-rpose of .this is to exhaust pressure from the conduits 53 and 53a, the reason for which will be made clear in the subsequent description of the operation.

During the forging operation, the valve member 56 is in raised position, being held in `that position in the manner above-described. With the valve member raised the inlet port 70 is in communication wit-h the `outlet port 7l, `and the exhaust port 72 is closed. Consequently, pressurized fluid is supplied to con-duits S3 and 53a, and the pressure in these conduits holds valves 5l and 51a open. The reason for providing .these valves will be made clear in the subsequent description of the operation.

Referring now to Fig. 4, ythere is shown the electrical system by which the electrically operated elements are controlled to effect the inching or jogging operation. The

solenoids

23 and 24, which are connected to the cyclic control apparatus 25 for effecting the cyclic forging operation, are also included in the control cir-cuits for the inching or jogging operation. A two-position manual switch 73, which may be a toggle switch, is set in one position for forging operation of the apparatus and is set in the other position for inching or jogging control. This switch has two

movable contacts

74 and 75 which are mechanically interconnected. It is shown in the position for the forging operation, in which position it serves to maintain relay 76 energized. This relay is initially energized by momentary 4closure of a reset switch 77 which is `biased to open position, and the relay locks itself in through contact 7S. With the relay energized, solenoid 69 is energized through contact 79 .and holds valve 54 open as above-described.

When it is desired to eiect inching or jogging operation, the cyclic control apparatus 25 is turned off and switch 73 is moved to its other position in which contact 74 is opened and contact 75 is closed. The opening of contact 74 causes deenergization of relay 76, whereupon

relay contacts

78 and 79 open and Contact 80 closes. The opening of contact 79 deenergizes solenoid 69, whereupon the valve 54 (Fig. 3) closes under the influence of weight 61, thereby shutting off the main uid supply line. Remembering that

contacts

75 and 80 are now closed, inching or jogging of either the right-hand impacter or the left-hand impacter may be eifectedby closure of switch 81 or S2. These switches are both dual contact switches, switch 81 comprising mechanically

interconnected contacts

83 and 84, and switch 82 comprising

interconnected contacts

85 and 86. Both of the

switches

81 and 82 are biased to the open position as by means of springs (not shown).

Y Closure of switch S1 energizes

solenoids

23 and 46. As previously described, and as may be seen in Fig. 3,

the energization of solenoid 23 effects opening of inlet valve 17 and closure of exhaust valve 18, while cnergization of solenoid 46 causes introduction of pressurized fluid through conduit 45, Linder control of orifice 50, to effect slow movement of the impacter 12. This pressurized fluid enters the cylinder 11 through port 41, and as the impacter 1,2 moves toward the right it uncovers port 16. Some of the pressurized fluid, therefore, flows through port 16 into chamber 15, and since valve 17 is open, it also flows into conduit 14 but is trapped by valve 51. This valve is closed under the influence of its spring, it being remembered that the pressure in conduit 53 has been exhausted through exhaust port 72 of valve 54.

The reasons for exhausting the pressure from conduits 53 and 53a and for providing the valves 51 and 51a may now be appreciated, Referring to conduit 53, for example, if the pressure therein were not exhausted preparatory to the inching or jogging operation there might be suflicient pressure remaining in this conduit to drive the impacter 12 forwardly at high velocity upon initial opening of the inlet valve 17 at the start of the inching operation. Exhausting the pressure from conduit 53 before commencement of the inching operation prevents this undesirable action from taking place. With the conduit 53 in communication with the exhaust port 72, the spring-closed valve 51 prevents pressurized fluid from flowing into the conduit 53 during the inching operation. As above-described, the pressurized fluid introduced during inching fills port 16 chamber 15 and conduit 14, but is trapped by the valve 51. Were it not for this valve the pressurized fluid could flow through conduit 53 and out through exhaust port 72, which would tend to defeat the inching operation.

Referring again to Fig. 4, closure of switch 32 effects energization of solenoid 23 and solenoid 46a, the latter corresponding to solenoid 46 and serving to control admission of pressurized fluid to the other cylinder 11a to effect slow movement of the other impacter 12a. The inching operation of the other impacter is the same as described above.

From the above description it will be seen that the manual switches 81 and 82 serve to control the inching operations of the respective impacters 12 and 12a. By operation of these switches the two impacters may be brought slowly to their meeting position as shown in Fig. 1.

Switch 87 is for the purpose of effecting return movement of the impacters. This switch comprises mechanically

interconnected contacts

88 and 59 which are biased to the positions shown. Operation of the switch effects opening of Contact 8S to render the jogging circuits inoperative and edects closing of contacts $9 to energize the solenoid 24. The energization of solenoid 24, as may be seen in Fig. 3, effects return movement of the impacters just as it does during the cyclic forging operation. Since solenoid 23 is now deenergized, the exhaust valve 18 is open to exhaust the previously admitted fluid.

Resumption of the forging operation of the apparatus is effected by returning switch 73 to the position shown, then momentarily closing switch 77 to energize relay 76 and thus energize solenoid 69, then manually raising lever S to effect latching of valve member 56 in open position, and finally starting the cyclic control apparatus 25. lt should be noted that resumption of automatic operation cannot take place until the operator has raised the manual lever 53. This is an important safety feature, as it insures against accidental starting of the automatic operation if the cyclic control apparatus 25 is started inadvertently, which might otherwise cause injury to a person inspecting or replacing the dies.

While a particular embodiment of the invention has been illustrated and described, the invention is not limited thereto, but contemplates such other embodiments or modifications as may occur to those skilled in the art.

I claim:

l. In combination, a fluid cylinder, a piston in said cylinder movable through a work stroke and a return stroke, a first conduit means for supplying pressurized fluid at high velocity to said cylinder so as to drive said piston through its work stroke, a second conduit means for supplying pressurized fluid to said cylinder so as to return the piston, means for controlling the flow of fluid in said first and second conduit means so as to effect repeated operation of said piston, a third conduit means for supplying pressurized fluid at low velocity to said cylinder so as to move the piston slowly in the direction of its work stroke, a valve in said first conduit means biased toward closed position, normally-energized electrical means arranged to hold said valve in open position, a valve in said third conduit means biased to closed position, normally-deenergized electrical means arranged to open said last valve, means operable at will to deenergize said first electrical means and thus close said first valve, and means operable at will to energize said last electrical means and thus open said last valve to effect slow movement of said piston.

2. In combination, a fluid cylinder, a piston in said cylinder movable through a work stroke and. a return stroke, a first conduit means for supplying pressurized fluid at high velocity to said cylinder so as to drive said piston through its work stroke, a second conduit means for supplying pressurized fluid to Said cylinder so as to return the piston, means for controlling the flow of fluid in said first and second conduit means so as to effect repeated operation of said piston, a third conduit means for supplying pressurized fluid at low velocity to said cylinder so as to move the piston slowly in the direction of its work stroke, a valve in said first conduit means biased toward closed position, a normally-energized solenoid, latch means actuated by said solenoid to hold said valve normally in open position, a valve in said third conduit means biased to closed position, a normally-deenergized solenoid arranged to open said last valve, means operable at will to deenergize said first solenoid and thus close said first valve, and means operable at will to energize said last solenoid and thus open said last valve to effect slow movement of said piston.

3. In combination, aV pair of horizontally aligned cylinders, a pair of opposed pistons in said cylinders movable toward one another in a work stroke and movable away from one another in a return stroke, a first conduit means for supplying pressurized fluid at high velocity to each of said cylinders so as to drive said pistons toward one another, a second conduit means for supplying pressurized fluid to each of said cylinders so as to return the pistons, means for controlling the flow of fluid in said rst and second conduit means so as to effect repeated operation of said pistons, a third conduit means for supplying pressurized fluid at low velocity to each of said cylinders so as to move the pistons slowly toward one another, valve means in said first conduit means biased toward closed position, a normally-energized solenoid, latch means actuated by said solenoid to hold said valve means in open position, valve means in said third conduit means biased to closed position, a normally-deenergized solenoid arranged to open said last valve means, means operable at will to deenergize said first solenoid and thus close said first valve means, and means operable at will to energize said last solenoid and thus open said last valve means to effect slow movement of said pistons toward one another.

4. In combination, a fluid cylinder, a piston in said cylinder movable through a work stroke and a return stroke, a first conduit means for supplying pressurized fluid at high velocity to said cylinder so as to drive said piston through its work stroke, a second conduit means for supplying pressurized fluid to said cylinder so as to return the piston, means for controlling the flow of fluid in said first and second conduit means so as to effect repeated operation of said piston, a third conduit means for supplying pressurized fiuid at low velocity to said cylinder so as to move the piston slowly in the direction of its work stroke, a valve in said first conduit means biased toward closed position but manually movable to open position, latch means for holding said valve in open position, a valve in said third `conduit means biased to closed position, means operable at will to release Said latch means and thereby effect closure of said first valve, and means operable at will to open said last Valve to effect slow movement of said piston.

5. In combination, a fluid cylinder, a piston in said cylinder movable through a work stroke and a return stroke, input and exhaust valves operatively connected to one end of said cylinder, conduit means for supplying pressurized fiuid at high velocity to the said end of said cylinder under control of the input valve, means including a solenoid for actuating said valves, means including another valve and an operating solenoid therefor for supplying pressurized fluid to the other end of said cylinder so as to return the piston, conduit means for supplying pressurized fluid at low velocity to the first end of said cylinder so as to move the piston slowly in the direction of its work stroke, a normally-open valve in said first conduit means to enable closure thereof, a solenoidoperated normally-closed valve in said last conduit means, manual-switch-controlled circuit meansffor energizing said first so-lenoid and the operating solenoid of said last Valve to efi'ect slow movement of said piston in the direction of its work stroke, circuit means for energizing said second solenoid, and manual switch means for simultaneously opening said first circuit means and closing said last circuit means to effect return of the piston.

6. In combination, a fluid cylinder, a piston in said cylinder movable through a work stroke and a return stroke, input and exhaust valves operatively connected to one end of said cylinder, conduit means for supplying pressurized fiuid at high velocity to the said end of said cylinder under control of the input valve, means including a solenoid for actuating said valves, means including another valve and an operating solenoid therefor for supplying pressurized fluid to the other end `of said cylinder so as to return the piston, cyclically-operable means for effecting timed intermittent energization of said solenoids so as to eect automatic repeated operation of said piston and adapted to be rendered inoperative at will, conduit means for supplying pressurized fluid at low velocity to the first end of said cylinder so as to move the piston slowly in the direction of its work stroke, a normallyopen valve in said first conduit means to enable closure thereof, a solenoid-operated normally-closed valve in said last conduit means, manual-sWitch-controlled circuit means for energizing said first solenoid and the operating solenoid of said last Valve to effect slow movement of said piston in the direction of its work stroke, circuit means for energizing said second solenoid, and manual switch means for simultaneously opening said first circuit means and closing said last circuit means to effect return of the piston.

7. In combination, a fluid cylinder, a piston in said cylinder movable through a work stroke and a return stroke, a first conduit means for supplying pressurized fluid at high velocity to said cylinder so as to drive said piston through its work stroke, a second conduit means for supplying pressurized fluid to said cylinder so as to return the piston, means for controlling the ow of uid in said first and second conduit means so as to effect repeated operation of said piston, a third conduit means for supplying pressurized fiuid at low velocity to said cylinder so as to move the piston slowly in the direction of its Work stroke, a normally open valve in said rst conduit means, a valve in said first conduit means between said first valve and said cylinder, spring biased to closed position when said rst valve is closed and opened by fluid pressure when said first valve is open, a normally closed valve in said third conduit means and means operable at will to close said first valve and open said second valve to effect slow movement of said piston.

References Cited in the file of this patent UNITED STATES PATENTS 254,741 Walsh Mar. 7, 1882 1,231,628 Lehr July 3, 1917 1,832,694 Ernst Nov. 17, 1931 1,905,065 Scholl Apr. 25, 1933 2,160,920 Strawn June 6, 1939 2,262,126 Whittles Nov. 11, 1941 2,375,946 Reichelt May 15, 1945 2,615,306 Alcorn, Ir. Oct. 28, 1952 FOREIGN PATENTS 430,825 Great Britain June 24, 1935