US2765162A

US2765162A - Ram mechanism with a quick release valve for adjustment of the stroke of the ram

Info

Publication number: US2765162A
Application number: US297815A
Authority: US
Inventors: Roy A Wulff
Original assignee: Electrol Inc
Current assignee: Electrol Inc
Priority date: 1952-07-09
Filing date: 1952-07-09
Publication date: 1956-10-02
Anticipated expiration: 1973-10-02

Description

Oct. 2. 19,56 R. A. wuLFF 2,765,162

RAM MECHANISM WITH A QUICK RELEASE VALVE EoR ADJUSTMENT 0E THE STROKE 0E THE RAM Filed July 9, 1952 2 Sheets-Sheet l HIS ATTORNEYS.

Oct. 2, 1956 R.

RAM MECHANISM WITH A QUICK RELEASE VALVE FOR A. WULFF ADJUSTMENT 0E THE STROKE oF THE RAM 2 Sheets-Sheet 2 Filed July 9, 1952 United States Patent V 2,765,162 l Patented Oct. 2, 1956 ice RAM MECHANISM WITH A QUICK RELEASE VALVE FOR ADJUSTMENT F THE STROKE OF THE RAM Roy A. Wulff, Hurley, N. Y., assignor to Electrol Incorporated, Kingston, N. Y., a corporation of Delaware Application July 9, 195.2, Serial No. 297,815

4 Claims. (Cl. 267--1) This invention relates to ram mechanisms for coupling two relatively movable members whereby the movement of one member can be transmitted to the other member with provision for release of the ram mechanism to allow relative movement between the members.

Many mechanical devices utilize the movement of one element through the medium of a linkage or the like to move ordisplace another element. Such positive linkages are well known and are entirely satisfactory when the movement of the two elements are always in the same relation. Some devices, however, require simultaneous movement of a pair of connected members during operation in one direction but also require freedom for relative movement between the members in the other direction or under other conditions of operation. For example, antiaircraft or automatic guns usually make use of the recoil of the gun to compress or wind a spring for actuating the loading mechanism by means of which a shell is fed into the breech of the gun during the counter recoil of the gun. The gun loader includes a shell magazine and a shell transporting member for transferring a shell from the magazine into the breech of the gun. The energy required to accomplish the loading of the gun is obtained from a large spring which is wound or compressedV by the recoil of the gun.

If the recoil of the gun and the movement of the shell loader were always the same, little dilculty would be encountered in coupling these two elements together. However, due to variations in shell loading, the recoil stroke of the gun may vary several inches. Moreover, the speed and extent of movement of the shell transporting member vary considerably. The speed of the shell transporting member does not vary from an expected speed a great deal when it is transporting a shell of the breech of the gun. However, it sometimes fails to pick up a shell and, being relieved of the weight of the shell, it travels at a much .higher speed and through a longer stroke than ordinarily.

The present invention relates to a coupling or ram mechanism by means of which the recoil of the gun may be transmitted to the shell loading mechanism to compress or wind the spring thereof. The ram mechanism then disconnects the gun from the shell loading mechanism and moves out of the path of the shell transporting member so that the latter is free to transfer a shell from the magazine to the breech of the gun during the counter recoil of the gun. Moreover, the coupling or ram mechanism is constructed and arranged so that it can release quickly to accommodate over-recoil of the gun and also 'to buler the over-recoil or an over-rapid movement of the shell transporting member.

The ram 'mechanism is arranged to collapse at high speed after cocking the shell loader so that during counter recoil movement of the gun, the ram is moved out of the pathvof the rapidly moving shell transporting member.

' The ram mechanism is further constructed and arranged so that it is extended to its original length during counter recoil of the gun to place it in condition for the shell loading mechanism during a succeeding recoil of the gun.

For a better understanding of the present invention, reference may be had to accompany drawing, in which:

Fig. 1 is a view in elevation of a typical quick release ram mechanism of the type shown in the present invention with the ram mechanism fully extended.

Fig. 2 is a view in section taken on line 2-2 of Fig. 1 with parts removed and broken away to disclose details of construction; and

Fig. 3 is a view in section through a modified quick release valve for the ram mechanism.

The form of the invention chosen for purposes of illustration is constructed for use in an automatic shell loading mechanism for an antiaircraft gun, but it will be understood that the device may be used with other mechanisms in which the relations of parts and their motions are similar. The ram mechanism includes a cylinder 10 for receiving a plunger or piston-piston rod assembly 11 which extends through one end of the cylinder and is reciprocable therein. As shown in Fig. 2, the plunger 11 includes a tubular piston rod 12 carrying on its inner end a sleeve 13 forming, in ellect, a piston but serving principally to guide the piston rod 12 in the cylinder. The piston sleeve 13 has an inturned flange 14 which bears against the inner end of the piston rod 12. The sleeve 13 has one or more grooves 15 in its edge allowing liquid to llow past it. The sleeve 13 is clamped in position on the end of the piston rod by means `ot a sleeve 16 having a closed inner end 17. The sleeve 16 is threaded into the inner end of the piston rod and is retained in position by means of a screw or key 18 which engages in the sleeve 13, the piston rod 12 and the sleeve 16. The sleeve 16 also has a llange 19 which abuts against the inner end of the llange 14 of the sleeve 13 and holds the latter in xed position. The right-hand end `of the sleeve 16 is tapered and forms a metering pin 2l), the purpose of which will be described hereinafter.

The piston rod 12 is guided in, and maintained in liquid-tight relation to, the end of the cylinder. Threaded into the left-hand end of the cylinder is a sleeve 21 having an enlarged flanged end 22 thereon whichV abuts against a collar 23 mounted on the outside of the cylinder 10. The inner end of the sleeve 21 forms an abutment for a packing 24 which surrounds the piston rod and prevents leakage therealong. The packing 24 is of the pressure type and is maintained in tight relation to the piston rod by means of a coil spring 25 which abuts against one yend of the packing and against a ring v26 in and bearing against the shoulder 27 in the cylinder 10. The enlarged head 22 of the sleeve 21 may also have the felt type packing 28 for rod lubrication and metallic wiper ring 29 which prevents foreign matter from being drawn into the cylinder as the rod is retracted.

The external sleeve has an inwardly extended flange at its left hand end which is notched to receive lugs 31 on the end of the cylinder, and prevents rotational movement of member 23 in relation to member 10. The sleeve 23 is retained against endwise movement to the left and right since the inwardly extended llange of member 23 is located between the enlarged head 22 on sleeve 21 and the left hand end of cylinder 10. The sleeve 21 is locked in position by means of a locking screw 31a.

The plunger assembly 11 is normally biased toward a retracted position from the projected position shown in Fig. l by means of a heavy spring 2, one end of which bears against the inner end of the sleeve 23 While the other end bears against a yoke or slide plate 33 slidably mounted on the cylinder 10 and connected by a pair of

spacer rods

35 and 36 to a cross plate or flange member 37 carried at the left hand end of the plunger assembly `11. The

rods

35 and 36 are guided in a cage 38 forming a part of the sleeve 23. As shown in Fig. l, the sleeve 23 has aligned bores in the pairs of oppostely directed

lugs

39, 40 and 41, 42 adjacent its opposite ends. The lugs 39 to 42 carry sleeve-like bushings or bearings 43 in which

fherods

35 and 36 slide. ASpacer sleeves 44 and .45 may be interposed between the sets of lugs.

The right-hand end of the cylinder, as viewed in Figs. l and 2, carries a housing member 50 which is provided with avpair of

parallel bores

51 and 52 adapted to receive respectively a quick release valve assembly 53 and a sliding piston 54. The housing 50 is mounted on the righthand end of the cylinder by means of a sleeve 55 on the casing which is screwed onto the end of .the cylinder and is retained in locked position by means of a locking nut 56. The lock nut may be keyed or pinned in position to prevent relative rotation of the cylinder and the casing. The connection between the housing and the cylinder also Aserves to position `in the right-hand end of the cylinder an orifice ring 57 having a metering port 5S therein. The ring 57 is screwed into and keyed to a sleeve 59 mounted inside the cylinder. The sleeve 59 has a flange 60 thereon abutting against the end of the cylinder. The iiange 60 is retained in engagement with the end of the cylinder by means of a shoulder or surface 61 at the inner end of the sleeve 55 on the housing 50.

As shown in Fig. 2, the bore 51 receives a valve casing 62 which has a port 63 substantially in alignment with a passage 64 in the side wall of the housing 50 and in communication with the interior of the cylinder through the metering port 58 and the sleeve 59. The port in the valve casing 62 communicates with a chamber 65 on one side of a partition 66 therein which forms a seat for a valve plug 67. The partition 66 has an opening 68 which connects the chamber 65 with a lower com- ',partment or chamber 69. The chamber 69, in turn, is

connected, by means of arport 70 in the wall of the valve casing 62 and a passage 71 in the wall of the housing 50 between the bores 51 .and 52, with the bore 52. The bore 52 and the .piston 54 therein form a reservoir for liquid. The outer end of the bore 51 is closed by means of a cap 72 to prevent the entry of dirt or the like.

The valve1unit53 is biased normally to a ,closed position .and is of the ,pressure unbalanced type whereby a `liquid ,pressure `in excess of .predetermined pressure will cause the valve to open. To this end, .the valve Aplug is .provided with a hollow `extension 7.5 rcarrying a piston portion 76 on its upper end. The .piston portion has a `sliding tit in a cylinder `sleeve 7.7 which `is `mounted in the upper wall 78 of the valve casing. The cylinder sleeve `77 has a peripheral ange 79 at its upper end which rests .against a shoulder 80 at the bottom of an internally `threaded bore 81 in the wall 7S ofthe valve easing. The sleeve 77 is retained in fixed position by means of an externally threaded `screw cap `82 which is threaded into the `bore 8.1 and pinned imposition. The cap S2 has a central opening .53 'therein to .permit air to ow into and out of the space above .the piston 76. The diameter of the piston 76 is `greater than the eiective diameter of the valve plug `67 so that pressure :in the chamber -65 wouldnormally tend to move the valve plug 67 away from the seat 66. The valve plug is, however, `normally maintained against its seat-66 by means of a spring 85 mounted in a bore 86 in the lower wall `87 of the valve casing and -bearing against a nut 88 threaded on the outer end of a valve stem 90 which-extends vdown from the valve plug 67 through the opening 68 and an opening 91 in the wall of the casing into the bore 86. To protect the spring, the stem may carry a hollow cylindrical shroud 92 between the spring 85 and the nut 38 which is slidable with the stem 90 in the bore 86 and `covers the spring 85.

The outer end of the valve stem may be provided with a hardened plug 93 for actuation of the valve by means of a cam 94, partially shown in dotted lines in Fig. 2.

The valve assembly or unit 53 has a -shoulder 95 on lower end of the valve casing 62 which abuts against a complemental shoulder 96 in the bottom of the bore 51. The end wall 87 of the valve casing has a reduced extension 97 thereon which extends through an opening 98 in the bottom wall of the casing 11 and receives a clamping nut 100 and washer 101 to retain the valve casing 62 in iixed position.

In use, the ram mechanism `described above is mounted on the recoil carriage of the gun by means of bolts passing through the

lugs

102 and 103 at the right-hand end of the housing 5) so that the device travels as a unit with the gun during recoil `and counter recoil. The left'- hand end of the plunger assembly including the cross plate 37 is adapted to engage the `cooking rmember of the gun loader, not shown. During the major portion of the recoil of the gun, the ram mechanism is maintained rigid because of the liquid trapped between the plunger and the valve unit 53, the latter normally being closed, as described above. Recoil movement of the gun, theretore, is transmitted directly tothe gun loader to cock it. At about the end of the recoil stroke of the gun, the valve 67 is displaced from its seat 66 by means of the cam 94 so that liquid can ow `out of the cylinder 10 through the metering port 58, the sleeve 69, .the passage 64, the port 63, the chamber 65, the open valve 66, 67, the chamber 69 and ports 70 and 71 into the reservoir chamber "52, thereby displacing the piston 54 and permitting the plunger to retract in the cylinder. Retraction of the plunger 1'1 is caused by the spring 32, the latter operating to retract the` plunger rapidly and thereby shorten or shrink the ram mechanism. The shrinking action begins before o r during the early stage of counter recoil of the gunso as to move the end of the plunger out of the path of the shell transporting element of the shell loadel thereby permitting the latter to move rapidly to feed the shell into the breech of the gun during the .counter recoil of the gun. During the last stage of counter recoil, the cross plate 37 `at the end of the plunger 11 comes up against a tixed stop, not shown, so that the continuing counter recoil of the gun will withdraw the plunger from the `cylinder and upon closingof the valve 53 by action of the cam 94 will lock the plunger in extended position, as shown in Fig. 1 ready -for another l.c ocking operation.

Sometimes the recoil of the gun .is more extended due to a greaterpowdercharge in a shell. To avoid damage to the gunloader andthe ram mechanism, the inward stroke `of the `plunger is buttered by action of the metering pin 20 `entering `theoritce.5,8. As the meteringpin 20 enters the orice 58 :it `restricts `the area through which liquid can How and therebyacts asa shock absorber. The metering pin and metering `oriiice.58 also .cooperate to 4cushion `the `stroke .of the `shell `transporting member, `if -it fails to pickzup a-shell Vand travels at :athigher speed thereby catching up with the .breech of `the :gun during an `early stage of the counter recoil movement of the gun. At this time, the `plunger has not been projectedand the metering pin and orifice act .'.toabsorb shock and `preventdamage when the loading mechanism strikes the plunger or cross plate 37.

The valve unit 53 also acts .to allow the plunger to be retracted .under conditions where the shell loader jams or too `great resistance is afforded by the shell loader. When the pressure in ,the cylinder and in the chamber 65 exceeds a safe maximum, `the `pressure on the piston 76 overbalances the Spring -so `thatthe -valve plunger 67 is unseated and the plunger can retract partially or fully, depending upon the Lperiod that the valve is open.

The valve structure ofitheram mechanism is susceptible to considerable modification. For example, if desired, a valve which is whollyfmanually 4or mechanically operated may be used yinstead .of ,a pressure unbalanced valve. Moreover, different forms .of pressure responsive `valves .may .be `usedinstead o'f the Yva'lveunit53 disclosed in Figs.

valve is 4illustrated in Fig. 3. "This .iform of valve includes a casing 110 similar to the valvecasing described above and mounted in the-bore 51 ofthe housing 50. The valve casing 110 has upper and

lower chambers

111 and 112 therein separated by a valve Seat partition 113 having an opening 114 connecting the

chambers

111 and 112. Cooperating with the valve-seat is a cone valve plug 115 carrying a piston 116 at its upper end, the diameter of the piston and the etective diameter of the valve being the same so that the valve and piston are in a pressure balanced condition. The piston is received in a cylinder bore 117 in the upper wall 118 of the valve casing and is normally biased toward the valve Seat 113 by means of a spring 119 bearing against the upper end of the piston. The springilis retained in a compressed condition by means of a spring retainer cap 120 threaded in the upper end of the enlarged bore '121. The valve plug 115 also has a hollow stem 122 extending downwardly therefrom through the valve opening 114 into a bore 123 in the lower wall 124 of the valve casing. The valve stem 122 has a smaller piston-like portion 125 in sliding engagement with the wall of the bore 123. The upper surface of the piston 125 is subjected to the liquid pressure in the chamber 112 and its lower surface can be subjected to the pressure in the chamber 111 in the manner described hereinafter.

The valve plug 115 has a series of radial ports 126 which communicate with the bore 127 in the valve stem 122 and an enlarged bore 128 in the upper portion of the valve and piston unit. Slidable in the bore 127 is a valve member 129 having a small piston portion 130 in liquidtight engagement with the wall of a bore 131 between the bores 127 and 128. The piston portion 130 has a valve plug 132 at its upper end engageable with the valve seat 133 formed at the junction of the bores 131 and 128. The effective area of the valve plug 132 is greater than the effective area of the piston 130 so that the iluid pressure exerted through the ports 126 normally tends to unseat the valve plug 132. To prevent leakage past the valve member 132, it carries an enlarged piston portion 134 which is in liquid-tight engagement with the wall of the bore 128. Moreover, the valve plug 132 is maintained against the seat under normal operating conditions by means of a spring 136 engaging the piston 134V and a spring retaining cap 137 threaded into the upper end of the bore 128. The Spring retaining cap 137 carries a spring tension adjusting plug 139 having an opening 140 therethrough to permit the space above the piston to be maintained at atmospheric pressure.

The valve and piston unit 132, 134, is provided with cross bores 141 which communicate with an axial passage 142 in alignment with a hollow plunger sleeve 143 mounted within the valve stem 122. The lower end of the sleeve 143 is provided with notches 144 to admit liquid between the end of the piston 125 and the end closure cap 145 which closes the lower end of the bore 123 and receives slidably a plunger rod 146 for unseatng the valve 115 by a cam or other means.

In operation, when the pressure in the chamber 111 exceeds a predetermined maximum controlled by the spring 136, the liquid acting through the ports 126 will unseat the valve plug 132, 134 and allow liquid to ow past the plug into the cross bores 140 and 141 and down through the passage 142, the sleeve 143 into the space below the piston 125. inasmuch as the valve plug 115 is essentially balanced by the piston 116, the pressure exerted on the piston 125 will be suicient to overcome the action of the spring 119 and thereby will cause the valve plug 115 to move away from the seat 113. Thus, the valve 115 is responsive to pressure and will open when the pressure in the ram mechanism attains a predetermined value allowing the plunger to retract to avoid damage to the mechanism. The valve is also controlled by a cam through the medium of the plunger 146 in the same manner as the valve disclosed in Fig. 2.

From the preceding description, it will be apparent that we have provided a mechanism which provides a rigid interlock between moving elements for transmitting motion from one element to another in one direction but allows relative movement between thev elements in the op'- posite direction. Moreover, it can release and contract to compensate for overextended movement of the driving member relative to the other member. It also provides for quick collapse of the ram mechanism to prevent interference between the parts and provides means whereby the ram mechanism can be restored to its initial condition ready for another power transmitting movement.

It will be understood that the mechanism is susceptible to modification in size and proportions and that other arrangements of valves and types of valves may be provided. Therefore, the form of the invention described herein should be considered as illustrative and not as limiting the scope of the following claims.

I claim:

l. A quick release ram mechanism comprising a cylinder to receive liquid, a plunger extending through one end of said cylinder and reciprocable relative thereto, spring means normally urging said plunger into said cylinder, means on said plunger engageable by a relatively movable part to move said plunger outwardly in said cylinder, a housing at the other end of the cylinder having a passage therein communicating with said cylinder, a reservoir communicating with said passage to receive liquid from said cylinder displaced therefrom by movement of said plunger into said cylinder, a normally closed check valve in said passage between said cylinder and said reservoir to prevent llow of liquid from said cylinder to said reservoir, and means adjacent to and outside of said cylinder for opening said valve to enable said spring means to move said plunger into said cylinder, said cylinder and said valve opening means being relatively movable.

2. A quick release ram'mechanisrn comprising a cylinder to receive liquid, a plunger extending through one end of said cylinder and movable therein between a projected position and retracted position, spring means normally urging said plunger toward its retracted position, means on said plunger engageable by a relatively movable part to move said plunger outwardly to said projected position, a housing at the other end of said cylinder having a passage therein communicating with said cylinder for admitting liquid into said cylinder and discharging liquid from said cylinder, a metering member having a restricted metering port therein interposed between said cylinder and said passage, a metering pin on said plunger movable into said port near the inner limit of the movement of the plunger to its retracted position to buffer the movement of the latter, a valve in said passage normally biased to closed position to prevent flow of liquid through said passage, and means to open said valve to enable said spring means to move said plunger to retracted position.

3. A quick release ram mechanism comprising a cylinder to receive liquid, a plunger extending through one end of said cylinder and movable therein between projected position and a retracted position, spring means urging said plunger to retracted position, means on said plunger engageable by a relatively movable part to move the plunger to projected position, a housing at the other end of said cylinder having a passage therein communieating with said cylinder for admitting liquid into said cylinder and discharging liquid from said cylinder, a metering member having a restricted metering port therein interposed between said cylinder and said passage, a metering pin on said plunger movable into said port near the inner limit of the movement of the plunger to its retracted position to buifer the movement of the latter, a valve in said passage normally biased to closed position to prevent ow of liquid through said passage and toy retain 'said plunger in projected position, and means responsive to increase in the pressure of the liquid in said.

passage yatreve la predeterminedpressure to opertsaid n valve to enable said spring to move said'plunge'r to ref tracted position in saiclfcylinder.r f

` 4. A quick release yram mechanism comprising a cylinK4 f der to receive liquid, a plunger extending through `one end of said'eylindery and movable therein between a projectedpnsition and a retractedposition, springmeansy f f normally urging said plunger toward its retracted position, meansy on said plunger engageable bya relatively movable part to move said'plunger to projected position,

a housing at the other end of said cylinder' havinga y passage therein communicating withy said cylinder for admitting liquid into said cylinder and discharging liquid from said cylinder, a metering member having a restricted y metering port therein interposedbetween said cylinder and said passage, a metering pin on said plunger movable into said port near the inner' limit oi"r the movement of the plungerto itsy retracted position kto buier the movef ment of the latter.y a valvein said ,passagey normally,

biased to' closed position to; prevent flow of yliquid through said nassage and to vretain said plunger in projected position, and means responsive kto yincrease yin the'presf f f sure of the :liquid in said passageabove a predetermined pressure to open said yvalve to enable said spring to rcn tract said plunger in `said cylinder.

v References Cited inthe tile of this patent i UNITED STATES PATENTS 2,072,099 Davison 'f f Mar. 2, i937 2,152,813y yMoore Apr. 4, 1939 2,196,068 Greve Apr; 2, 1940 2,332,520 Luchty e-- Oct. 26, 1943 2,445,053 Allin 11115113, 1948' 2,453,830 Chadwick et al Nov'.y i6, 'i948 2,500,459 Hoover et al. f g.- Mar.y 1,4, i950 i N FOREIGNiPATENTs i