US3470788A

US3470788A - Revolver type semiautomatic firearm

Info

Publication number: US3470788A
Application number: US716931A
Authority: US
Inventors: Viljo Niilo Virtanen
Original assignee: Individual
Current assignee: Individual
Priority date: 1968-03-28
Filing date: 1968-03-28
Publication date: 1969-10-07
Anticipated expiration: 1986-10-07

Description

1969' v. N. VIRTANEN REVOLVER TYPE SBHIAUTQIATIC FIREARM 2 Sheets-Sheet 1 Filed larch 28. 1968 INVENT OR ATTORNEY- Oct. 7, 1969 v, vm'r 3,470,788

REVOLVER TYPE SEMIAUTOIATIC FIREARM Filed larch 28. 1958 2 Sheets-Sheet 2 2" 'IIIIIIIIIIIIIIIII I FIG.7

INVENTQR N-Vil'tflflen ATTORN EYS United States Patent 3,470,788 REVOLVER TYPE SEMIAUTOMATIC FIREARM Viljo Niilo Virtanen, Sornaisten rantatie 3 A 24, Helsinki 53, Finland Filed Mar. 28, 1968, Ser. No. 716,931 Int. Cl. F41c 1/02 US. Cl. 89-155 7 Claims ABSTRACT OF THE DISCLOSURE A semiautomatic revolver-type firearm having a barrel fixed to a frame and a cartridge cylinder rotatable on the frame adjacent the breech end of the barrel. A hammer controlled by a trigger mechanism is automatically recocked after each firing by a movable slide displaced rearwardly by the recoil of a cartridge fired in a cartridge chamber of the cylinder aligned with the barrel. The firearm is initially cocked by manual retraction of the slide by a manual cocking lever. Interlocking means included in the trigger mechanism and coacting with the slide precludes release of the hammer from its cocked position when the slide is retracted. Detent means on the frame coacts with a cylinder rotating mechanism to assure rotation of the cylinder only in a normal direction and the slide functions upon moving rearwardly and then forwardly to rotatably index the cartridge cylinder forwardly by means of the cylinder rotating mechanism. Releasable detent means on the frame coacts with the slide to controllably retain the latter in either of two retracted positions, one of which permits free spinning of the cylinder in its normal direction of rotation and the other of which holds the slide releasably in a non-firing position for single shot usage of the firearm.

This invention relates to a semiautomatic revolver-type firearm in which the rotation of the cartridge cylinder is effected by a spring actuated slide, which in turn is moved by the recoil action.

Conventional semiautomatic revolvers have several defects. One of the most serious ones is that the cylinder rotates partly or completely whilethe bullet still is inside the barrel. Since the rotating mechanism receives its energy from the backward movement of the cartridge case the impetus of the cylinder may cause such a sudden and heavy stress on the gun parts that they cannot resist it, or then the kinetic energy imparted by the recoil to certain gunparts will be insufficient to cock the gun. It may even happen that the cylinder will prematurely rotate into its new position before the bullet has even reached the barrel, which will cause an inside explosion within the gun. Another disadvantage of said conventional constructions consists in the completely unsolved problem how one should ensure that the cartridge case will remain undamaged when under pressure the same begins its backward movement simultaneously with the bullet moving forward. In some semiautomatic guns having ammunition boxes the problem is solved by allowing the complete barrel-and-lock assembly to move together backward, giving the bullet time to leave the cartridge case. A disadvantage of such guns is, however, that the barrel movement will disturb aiming accuracy, and also that the moving masses are unnecessarily heavy causing a disturbing movement when the gun is fired. A further disadvantage of some semiautomatic revolvers is that the hammer must generate the rotation movement of the cylinder besides discharging its primary function, and therefore it cannot move freely.

It is the object of this invention to eliminate these disadvantages, the novel feature of the firearm being that the slide in moving backward is adapted to cock the hammer, and, additionally, to cock a spring activated cocking lever movably jointed to the slide and instrumental in performing the initial cocking of the gun and in executing the return movement of the slide. By means of the trigger mechanism the hammer and the cocking lever are jointed to each other in such a way that the hammer will remain cocked irrespective of the position of the trigger, while the slide, without causing the cylinder to rotate, will impart a rotating movement to a cylinder-rotating mechanism placed inside the cylinder, and further the slide will, on returning to its initial position turn the cylinder-rotating mechanism in the opposite direction, the said rotating mechanism having been coupled to the cylinder.

A semiautomatic revolver type gun built according to the teaching of this invention will be reliable in operation, since during the fast and sudden movement caused by the created pressure the slide only will move backward, its movement being softened by the thereto attached spring of the cocking lever. The slide is connected to a gear bush of only low inertia and the same moves along a slot in the latter, this slot firstly running parallel to the longitudinal axis of the gear bush, then spirals along the cylindrical surface and ends in a straight line again. This creates a small gear bush torque requiring only very little energy. Moved by energy of the spring mechanism of the cocking lever the slide returns to its initial position while turning the cylinder, by means of the gear bush mechanism, simultaneously to a new position. The hammer has no other function but to ignite the charge.

Another advantage of the gun is it will not go off e.g., it dropped to the ground, because the gun has a built-in hammer protected from shocks. Also, when the gun is cocked, the cylinder is always locked and cannot be rotated forward. When the slide is pulled back to safety position the cylinder is free to rotate in its normal direction, thereby rendering it possible to load and to empty the cylinder in this position. The safety position can readily be observed because the slide is disconnected from the cylinder and invisible within the frame. The breech distance equals zero because a spring will .at all times urge the slide against the bottom of the cartridge case therefore, on firing the case cannot hit the slide with force. Further, the cylinder need not always be a full cylinderit can be used as partial cylinder, e.g., for receiving only two or three cartridges as is the case in some semiautomatic shotguns for hunting.

In order to avoid gas losses and bursting of cartridge case, in bigger calibred guns the slide may, when in closed position, be arranged to press against a removable cartridge chamber, provided with a packing bushing and with springs, inserted into the bore of the cylinder. In this case, when the charge is ignited the pressure will cause the chamber and the case to move backward together, the case thus remaining motionless in relation to the chamber wall for the time needed by the bullet to detach itself from the case, the friction created preventing case from tearing, and the packing bushing preventing gas losses that would reduce muzzle velocity of the bullet, while, pushing the breech device (the slide) backwards until the chamber stops, the case continuing its movement until stopped by the case block and the slide still continuing its movement until finally, induced by the spring mechanism of the cocking lever, said slide returns to its initial position. While performing this return movement, the slide with the help of the gear bush mechanism rotates the cylinder into a new position.

The accompanying drawing shows an embodiment of the invention, where:

FIG. 1 is a side elevational view of the firearm;

FIG. 2 is a vertical sectional view of the cartridge cylinder showing the rotating mechanism located in its center;

FIG. 3 is a vertical rear end view of the cylinder showing the cartridge chamber bores, the central bore and the guiding bars of the slide with their locking slots.

FIG. 4 is a vertical side view showing, partially in section, the slide mechanism, the hammer, the cocking lever with spring mechanism and trigger mechanism;

FIG. is a horizontal top view and a vertical front end view of the slide safety gear and the case block;

FIG. 6 is a vertical, partly sectional side view of the detachable cartridge chamber fitted into a sectional view of the cylinder. Part of the barrel and of the frame are visible, partly in sections.

FIG. 7 shows the bipartite slide, the moving end thereof, partly in section.

In FIG. 1 detail 1 is the frame of the gun on which barrel Is is mounted. Into aperture 1a is mounted cartridge cylinder 2 supported by and rotating on spindle 6. Behind aperture 1a and centering to barrel axis is another aperture 1b for case block 12. Behind the latter is a third opening for safety catch 13. Above the safety catch and movable in longitudinal frame opening is cocking lever 17 of the gun. Hammer 38 which is located completely inside the frame, is shown in FIG. 4. Below the frame and inside the trigger guard 1 are trigger 27 and counter trigger 34 attached to the frame. The counter trigger 34 increases sensitiveness of first trigger 27. Adjusting screw 45 in a threaded bore in front part of trigger guard is used for adjusting of counter trigger 34. In front of the cylinder is shown cylinder safety catch 8, the lower part of which is fixed to the frame while hooklike upper part of the same reaches to the gearing 4a of gear bush 4 (FIG. 2) which rotates cylinder. In front of the safety catch peg 5b is fixed transversely to the frame, said peg locking the cylinder spindle to its place.

As shown in FIG. 2 the rotating mechanism of the cylinder is mounted on spindle 6 which attaches cylinder to the frame. The cylinder is rotated by gear bushings 3 and 4 mounted on said spindle. Of these, bushing 4 is fixed to the cylinder by means of groove 4b in the cylinder and a corresponding ridge on the bushing. Contrarily, bushing 3 is freely movable in center bore of the cylinder. Additionally, both bushings are torsionally turnable on spindle 6, bushing 3 moreover movable lengthwise on said spindle. For torsional movement bushing 3 is provided with slot 3a near its rear end, cam 11 on underside of slide 9 fitting into said slot 3a (FIG. 4). Said slot 3a in surface of bushing consists of two straight lengths with connecting spiral line part in middle. The spacing between both ends of said slot is same as spacing of cartridge bores of cylinder. Slide cams movement from end to end of slot then causes torsional turning of bushing, turned angle corresponding to slots spacing. End of bushing 3 opposite bushing 4 is formed to one side oblique gearing into which will fit corresponding gearing of bushing 4. In order to ensure turning in one direction only of bushing 4 and of cylinder attached thereto, gearing 4a of bushing 4 is of a type which hook 8 in frame (FIG. 1) will allow to turn in one direction only. To support described bushing construction, front end of spindle 6 carries a third bushing 5 with bore 5a, spindle 6 being provided with a cut (not shown) located correspondingly. By means of trunnion 5b (FIG. I) inserted in a bore in gun frame, the cylinder with its spindle are fixed to gun and the bushing arrangement is supported on spindle. In bushing end spindle 6 additionally carries spring 7 leaning against shoulder on spindle, said spring at all times urging bushing 3 against middle bushing 4 in such a way that when oblique gearing slips over it, said bushing yields elastically, but turning in opposite direction makes oblique gearing rigidly enough couple bushings together.

In accordance with FIGS. 2-3 the cylinders rear side is provided with stop ridges 2a located in pairs on each side of cartridge chambers. Thus, slide occupying forward position cam 11 on same is braced against the sides of corresponding groove, keeping the cylinder immovable when a shot is fired.

FIG. 4 is a side view showing, partly in section, the slide, trigger and sear mechanism, in aperture 1a belonging cylinder omitted. Slide 9 is fitted to move behind cylinder in slot made in barrel extension. Front part of slide holds a conventional nest 10 for hammer, cam 11 being located to begin from hammers front end. The purpose of cam 11 has been explained above. In rear end of slide, behind hammer, out 9b provides space for the movement of hammer 38 which is jointed to the frame by pin 39. In the vicinity of the rear end, at a right angle to the cut is shown another cut 9a into which is fitted an up and down movable guiding part (not shown), whereto cocking lever 17 is jointed by means of pivot pin 18. Said cocking lever 17 is jointed to the frame by means of pivot pin 19. By pins 20a and 20b linking part 20 connects cocking lever with spring adjuster 21, which in turn is fixed to frame by pin 22. Compressing spring 24 exerts pressure via spring rod 23 on spring adjuster and thereby on cocking lever and slide. When centers of

pins

20a, 20b and 22 form a straight line, spring pressure reaches its maximum (cocking lever is motionless), but pressure ceases proportionally as pin 20b is moved in direction from left to right in FIG. 4. By pivot pin 26 to frame fixed releasing lever 25 makes possible the functioning of the trigger and cooking mechanisms proper. Transversely in both ends of releasing lever 25 are pegs of which one engages not-ch in bottom end of cocking lever and the other one in moving up and down imparts movement to sear releaser 30. Pushed by spring 28 releaser hook 30a catches trigger 27 which is fixed to the frame by pivot 31. Sear releaser 30 is jointed to one end of sear 32 by pin 31 and will move the distance necessary Within a slot made in trigger. Pushed by spring 36 upper end of sear 32 engages sear shoulder 38a of hammer 38, while the other end of said spring presses against sensitizing counter trigger 34 which pivots on its to the frame fixed pivot pin 35. Sear 32 is jointed to the frame by pin 33. Upper end of hammer spring 40 is braced against peg 3812, the necessary cut for the spring having been made in hammer.

FIG. 5 shows slide with gearing grooves 9c and 9d which arrest hook in end of safety catch 13. Frame cut 10 for safety gear is formed to rise in forward direction in such a way that when lever 14 is pushed to front end of safety catch, hook will not contact slide 9. The safety gear is fixed to the frame by pin 15. Bore in the opposite end of safety gear holds compression spring 16 which leans against frame and urges safety gear into safety position. Cut 1b in frame (FIG. 1) holds case block 12 which runs partly also in groove in slide side surface.

FIG. 6 shows (partly in section)

removable cartridge chambers

41, 42, 43 especially intended for bigger calibre guns. The chamber formed by an in cylinder bore removably inserted socket-like part of a size corresponding to calibre of gun, thinned in rear end to protrude slightly from cylinder plane, is leaning against shoulder in cylinder bore. Compression spring 42 and packing bushing 43 are inserted in thinned front end of said part. Compression spring pushes packing bushing against barrel and the chamber against said shoulder in cylinder bore-the chamber being dimensioned to leave a narrow slit between chamber and barrel to enable cylinder to rotate. FIG. 6 shows partly in section expansion in rear end of barrel into which fits front end of chamber. Pushed by slide, front end of chamber either moves into said barrel expansion or will press tightly against rear end of barrel when shot is fired. Chamber recoil caused movement backward lasts a moment only, yet long enough for bullet to leave case without damaging itfor the time of this movement case remains in contact with chamber walls. When bullet has left, pressure ceases and chamber movement stops but case movement continues as well as slide mechanism movement caused thereby.

Bipartite slide used in bigger calibre guns as well as its movable end 9 is shown in FIG. 7, partly in section, the slide mounted on end thinned for that purpose. This movable end is able to perform a to-and-fro movement of a fixed length within a part 1d of slide bore widened for that purpose, this robust end also functioning as case block more reliably than the case blocks used in smaller calibre guns; where case block 12 is satisfactorily reliable and does not require change in form of case and its bottom. Necessary friction is provided by two springs (not shown) which make end 9 function without disturbances.

The gun works as follows: when cocking lever 17 is pulled backward by its spur, slide 9 moves backward simultaneously moving hammer 38 into cocked position. The movement of cocking lever 17 sets spring 24, the tension of which can be kept almost constant, and even corresponding to initial tension, in various positions of the spring, by the use of adjusting lever 21. End of releasing lever 25 in notch of bottom part of cocking lever 17 now moves upward causing its other end to push sear release 30 free from contact with trigger 27. Spring 36 now moves upper end of sear 32 against cocking shoulder 38a thereby cocking hammer 38. While slide 9 moves backward its cam 11 moves in slot 3a in surface of bushing 3, firstly parallel to spindle so long a distance that the end of slide 9 is released from locking bars 2a, then proceedin spiral formed part of slot in bushing simultaneously turning bushing the angle of one spacing step. Owing to the resistance of gearbush hook 8 and gearing 4a of counterbushing 4 cylinder 2 has not moved from its position. By means of ridge 4b of the cylinder the counterbushing 4 and the cylinder are immovably anchored to each other.

During return movement of cocking lever 17 cam 11, moving in slot 3a, turns bushing 3 the angle corresponding to the spacing of slot 3a, simultaneously and coupled by the gearing of the gear bushings, cam 11 turning cylinder as well to a new position. Now the gun is cocked for firing-finger possibly on trigger should be moved forward to let spring 28 actuate trigger 27 forward and hook 30a of sear release 30 to engage trigger. Counter trigger 34 being pushed forward, cocking shoulders of sear 32 and hammer 38 move as near shot release point as possible, shortening firing movement of trigger 27. Adjustable by means of screw 45, the functioning of the countertrigger brings the advantage that upper end of sear 32, ie the cocking hook, when engaging hammers cocking shoulder 38a, can penetrate to the bottom, making the gun remain cocked in spite of the jolt caused by shot fired, yet easy to fire thanks to counter trigger. When charge is ignited by blow of hammer 38 on striker the case tends to move backward, causing same sequence of movements as above, starting from pulling the spur of cocking lever 17, the case however stopping at case block 12. If the case block is so far back that the case completely leaves the cylinder the case will fly off from gun, whereas, if the case block is so placed that a part of the case remains in cartridge'chamber, the case Will remain so, but it is easily detachable by hand. This brings the advantage that the cases will not fly about or inconvenience the man next to the marksman. The ceases also remain faultless for reloading.

When the charge is ignited a strong pressure will hit the wall of the case itself, and also cause strong friction in the case wall. The case may even burst or break. But if the cartridge chamber 41 is movable longitudinally it is possible to prevent case bursting, since for a moment the case moves backward together with the cartridge chamber, giving the bullet time to leave the case.

The guns way of functioning is regulated from the safety gear. The safety gear lever 14 is moved right to pin 15 which allows spring 16 to urge hook of safety catch 13 towards the slide. When slide 9 is moved backward by spur of cocking lever 17, the hook of safety catch 13 firstly takes hold in groove 90. This allows cylinder to rotate in its normal direction and the chambers may be loaded with cartridge. Thereafter the spur is pulled fur-- ther backward until the hook of safety catch 13 takes hold in groove 9d. The slide 9 is now in its backward position. Pushing the rear end of safety gear releases the hook and the slide can return to its initial position. All the movement sequences previously described have been carried out and the gun may be fired. Thereafter the slide 9 automatically moves to its backward position. If you want the slide automatically and immediately to return to its initial position, you have only to move lever 14 toward the hook.

The invention is claimed as follows.

1. A semiautomatic revolver-type firearm comprising in combination a frame, a barrel fixed on said frame, a cartridge cylinder defining an annular series of angularly spaced cartridge chambers rotatably mounted on said frame and disposed at the breech end of said barrel, a hammer movable between a cocked position and a firing position for firing a cartridge in said cylinder, first spring means for urging said hammer from said cocked position to said firing position thereof, a trigger mechanism coacting with said hammer to releasably retain the latter in said cocked position thereof and including a trigger operable normally to release said hammer for spring movement from said cocked position to said firing position, a slide movably mounted on said frame for movemen: between a normal forward position and a rearward retracted position, second spring means coacting with said slide to urge the latter to its forward position, said slide coacting with said hammer to cock the latter as an incident to retraction of the slide, a manual cocking lever coacting with said slide to effect manual retraction of the latter to cock the firearm whereupon the slide is returned to its normal forward position by said second spring means, said slide coacting with said cartridge cylinder to be moved rearwardly to its retracted position by the recoil of a cartridge fired in said cylinder thereby effecting cocking of said hammer, said trigger mechanism including linking means interconnected between said movable slide and said hammer to retain the cocked hammer in its cocked position independently of the position of the trigger while the slide is retracted from its normal forward position, a cylinder rotating mechanism disposed within said cylinder, said cylinder rotating mechanism including cylinder rotating means coacting with said slide to be rotated by the latter as an incident to rearward movement of the slide without rotating the cylinder, and said cylinder rotating means coacting with said slide and said cylinder to rotatably index the latter as an incident to forward movement of the slide to its forward position.

2. A firearm according to claim 1 in which said cartridge cylinder defines a central bore generally coaxial therewith, said rotating mechanism is disposed in said central bore of said cylinder, a spindle is supported on said frame and said rotating mechanism is mounted on the spindle, said rotating mechasism including an axially movable gear bushing defining thereon a cylindrical surface and defining therein a cam slot having a portion thereof extending axially with respect to the gear bushing and having another portion of generally helical shape extending along the gear bushing, a cam on said slide movably engaging said cam slot for imparting to said bushing a rotary movement corresponding to the angular extent of said cam slot about the axis of said gear bushing, said rotating mechanism including a counter gear bushing disposed in coaxial alignment with said gear bushing, said gear bushing and said counter gear bushing having adjacent ends defining coacting gears shaped to transmit rotary motion of said gear bushing to said counter gear bushing in one direction while allowing free rotation of said gear bushing relative to said counter gear bushing in the opposite direction, said coacting gears having a plurality of angular spacings respectively equal to the angular spacings of said cartridge chambers in said cylinder, a compression spring mounted on said spindle and coacting with said gear bushing and said counter gear bushing to urge said bushings into yieldable engagement with each other, said gearing on said gear bushing and gearing on said counter gear bushing thereby continuously conditioning said gear bushing to turn said counter gear bushing in said one direction while allowing said gear bushing to rotate in said opposite direction relative to said counter gear bushing, said counter gear bushing defining thereon a protuberance, said cartridge cylinder defining a slot receiving said protuberance on said counter gear bushing to preclude relative rotation of said cylinder and said counter gear bushing, a detent mounted on said frame, gearing rotatable with said counter gear bushing and coacting with said detent to preclude rotary indexing of said cylinder in said opposite direction and to allow rotary indexing of said cylinder in said one direction, an anchoring bushing disposed in said frame and receiving said spindle in contact with said counter gear bushing, said anchoring bushing defining a peg bore therein, said spindle defining a peg notch aligned with said anchoring bushing bore, said frame defining a peg bore aligned with said peg bore in said anchoring bushing, a peg extending into said peg bore in said frame, and said peg bore in said anchoring bushing and said peg notch in said spindle to attach said rotating mechanism to said frame and prevent rotation of said spindle relative to the frame.

3. A firearm according to claim 1 in which said hammer is supported on said frame by a pivot pin and said slide defines a cut therein for receiving the hammer, said hammer defines a sear shoulder thereon; said trigger mechanism including a sear, a pin pivotally supporting said sear and a spring urging said sear into engagement with said sear shoulder on the hammer to retain the hammer in cocked position; a pivot pin supporting said trigger on said frame, said trigger mechanism including a scar releaser pinned to said sear and having a hook cooperating with said trigger to effect in response to actuation of said trigger release of said hammer from said cocked position thereof for movement of said hammer by said first spring means to said firing position, a firing pin disposed at the rear of said cylinder for engagement by said hammer to fire a cartridge in the cartridge chamber aligned with said barrel, said cocking lever having a pin thereon coacting with a slot in said slide to effect by means of said cocking lever manual retraction of said slide to initially cock the firearm, said cocking lever being swingably supported on said frame by a pivot pin, said linking means in said trigger mechanism includes a releasing lever pivotally supported on said frame and coacting with said sear releaser, said releasing lever having a pin thereon coacting with a notch in said cocking lever to actuate said releasing lever when said slide is retracted from its forward position to render said trigger inoperable to actuate said sear releaser to release said hammer from its cocked position while said slide is retracted from its forward position.

4. A firearm according to claim 1 in which said cylinder defines in the rear end thereof a plurality of guiding bars intervening between the successive cartridge chambers and being separated successively by locking recesses therebetween, said slide defines on the underside thereof a cam positioned to fit into a locking recess in said cylinder aligned with said cam when said slide is in its forward position to fix said cylinder against rotation with the corresponding cartridge chamber aligned with said barrel.

5. A firearm according to claim 1 in which said slide comprises a forward first part adjacent the rear end of said cylinder and a second part extending rearwardly from said first part, said second slide part having a forward end thinned and engaging said first part in movable relation thereto, said frame defining therein a bore receiving said first slide part and being dimensioned to allow rearward movement of said first slide from its forward position to an extent which is limited to a range less than the range of rearward movement of the second slide part.

6. A firearm according to claim 1 in which said slide defines in one side thereof a longitudinal slot, said frame defines a frame slot aligned with said last mentioned slide slot, a case lock is fixed to said frame in said last mentioned frame slot and extends into said last mentioned slide slot to determine a rearmost cartridge position to which a cartridge fired in said cylinder can recoil against said slide.

7. A firearm according to claim 1 in which said slide defines on the forward end thereof slide arrest grooves, a safety catch, a pin pivotally supporting said safety catch on said frame, said safety catch having on a forward end thereof an arrest hook aligned with said slide arrest grooves, a spring coacting with said safety catch to urge the latter swingably in a direction to engage said arrest hook thereon with either of said arrest grooves in said slide when the latter is in a retracted position thereof, limit stop means movably supported on said safety catch for adjustable displacement therealong, means on said frame coacting with said limit stop means when the latter is adjusted to a position thereof near said arrest hook to hold said arrest hook in an inoperative position free of engagement with said arrest grooves so that said slide can move in either direction free of restraint by said safety catch, said limit stop means when adjusted to a position remote from said arrest hook releasing said safety catch to engage said arrest hook selectively with one of said arrest grooves when said slide is in a first slide position to allow said cartridge cylinder to rotate freely in said one direction and to engage said arrest hook with the other arrest groove when said slide is in a second retracted position to hold said slide against forward return movement for controlled subsequent release by said safety catch for single shot functioning of the firearm.

References Cited UNITED STATES PATENTS 726,109 4/1903 Stow 89-155 X BENJAMIN A. BORCHELT, Primary Examiner STEPHEN C. BENTLEY, Assistant Examiner US. Cl. X.R. 4265