US3714860A - Primer metering apparatus for ammunition loading machines - Google Patents

Abstract

AN AUTOMATIC LOADING APPARATUS FOR SMALL ARMS AMMUNITION INCLUDING A HORIZONTALLY AND CYCLICALLY DISPLACEABLE TRANSPORT MEMBER FOR METERING PRIMERS FROM A GRAVITY-FEED VERTICAL SUPPLY STACK TO A WORK STATION WHEREIN THE DRIVE MEANS FOR THE TRANSPORT MEMBER INCLUDES A SPRING FOR RESILIENTLY BIASING THE TRANSPORT MEMBER INTO ENGAGEMENT WITH A PROGRAMMING CAM DURING MOVEMENT TOWARD THE WORK STATION, WHICH CAM POSITIVELY DRIVES THE TRANSPORT MEMBER BACK TO THE SUPPLY. APPARATUS FOR VACUUM CLEANSING THE METERING AREA IS PROVIDED. AN AUTOMATIC POWER INTERRUPTION FEATURE IS PROVIDED WHEREBY THE DRIVE MOTOR POWER IS INTERRUPTED IN THE EVENT THE TRANSPORT MEMBER FAILS TO MOVE OUT OF THE PATH OF A SWITCH CARRIED BY AN UPPER PLATEN ASSEMBLY WHICH FORMS PART OF THE DRIVE MEANS.

Description

' FeB. 6; 1973 R. A. LEICH' 3,71

PRIMER METERING APPARATUS FOR AMMUNITION LOADING MACHINES Filed May 13, 1971 2 Sheets-Sheet 1 IN VENTOR zoerf .4 Lez'c ATM)! II IL Y",

Feb. 6, 1973 R. A. LEICH 3,714,860

PRIMER METERING APPARATUS FOR AMMUNITION LOADING MACHINES Filed May 13, 1971 2 Sheets-Sheet 2 RESiET RELAY H5 A C INPUT 1/8 4 mil! Hm;

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ATTORNEY United States Patent 3,714,860 PRIMER IVIETERING APPARATUS FOR AMMUNI- TION LOADING MACHINES Robert A. Leich, Sonthfield, Mich, assignor to Camdex Inc., Detroit, Mich. Filed May 13, 1971, Ser. No. 142,955 Int. Cl. F42b 33/04 US. Cl. 8623 12 Claims ABSTRACT OF THE DISCLOSURE An automatic loading apparatus for small arms ammunition including a horizontally and cyclically displaceable transport member for metering primers from a gravity-feed vertical supply stack to a work station wherein the drive means for the transport member includes a spring for resiliently biasing the transport member into engagement with a programming cam during movement toward the work station, which cam positively drives the transport member back to the supply. Apparatus for vacuum cleansing the metering area is provided. A11 automatic power interruption feature is provided whereby the drive motor power is interrupted in the event the transport member fails to move out of the path of a switch carried by an upper platen assembly which forms part of the drive means.

This invention relates to ammunition loading machines and particularly to an improvement in such machines whereby the risk of a primer explosion during loading operations is greatly reduced, if not eliminated.

In the loading of small arms ammunition, i.e., rifle, pistol, and shot-gun shells, it is necessary to assemble a primer and a cartridge or casing as well as to fill the cartridge or casing with powder, shot, or lead and to suitably crimp or close the cartridge or casing to provide a closed package. In reloading operations applied to previously-used cartridges or casings, the additional step of removing the old primer is also required.

The primer itself is a small cap or wafer which is filled with a percussion powder so that upon application of pressure by means of a hammer or firing pin, a small explosion occurs, this explosion being efiective to trigger the ignition of the larger quantity of powder in the shell itself, thus, producing the gaseous expansion which propels the shot or slug through the barrel of the gun. If, during such loading operations as are carried out by automatic loading machines, a positively driven machine element is caused to apply pressure to an improperly positioned primer, an explosion is likely to occur in the loading apparatus itself. This normally occurs only if a primer feed operation, for example, fails to function properly or, in the case of automatic reloading apparatus, a spent primer is not properly removed from a cartridge being reloaded. The danger of a primer explosion in the loading apparatus is particularly acute where a vertical stack of primers is employed as a gravity fed supply to the machine. Under these circumstances, the explosion of one primer can easily trigger the explosion of all primers in the supply, thus, giving rise to an explosion of considerable proportions.

In accordance with the present invention, an improvement to automatic loading machines is realized, this improvement being such as to greatly reduce, if not eliminate the possibility of primer explosions in the loading phases due to pressure being applied to a primer by a driven machine element, such as a metering member. This is accomplished by means of a primer transport member which operates to cyclically transport primers from a supply point to a work station and by improved drive means for such transport member, this drive means being such as to resiliently urge the transport member toward the work station but to positively drive the member from the work station back toward the supply. Accordingly, the resilient drive force is such that the presence of a primer in a position which interferes with the transport member simply causes the transport member to stall, thus, interrupting loading machine operation. This is to be contrasted to prior art machines wherein a transport member is positively driven from the supply point to the work station, thus, creating the possibility of the application of positive and full machine pressure to a primer in a jamming position.

In accordance with another aspect of the invention, the possibilities of an improper primer metering operation are substantially reduced by eliminating the possibility for the accumulation of foreign particles, such as dirt and excess primer powder, in the primer metering area. In accordance with a specific form of the invention as hereinafter set forth in detail, this is accomplished by providing a vertical receptacle aperture in a primer transport member which receptacle aperture is aligned in the primer pick up or acceptance position with a vertical supply stack on one side and a small aperture in a support member on the other side. The small aperture in the support member is suitably interconnected with a vacuum pump for the purpose of causing an air flow through the transport member receptacle aperture and through the aperture in the support member, thus, clearing the area of foreign particles, such as dirt and excess primer powder which might otherwise collect in excess quantities over a substantial period of operation.

According to a still further aspect of the invention, power interrupt control means are provided for monitoring the displacement of a primer transport member such that in the event the transport member fails to be replaced from a primer acceptance or supply position toward a work position as a portion of the drive means having a synchronized program of displacement move toward a predetermined position, the motive power source of the drive means is momentarily rendered inoperative. In the illustrative embodiment of the invention hereinafter set forth in detail, this is accomplished by means of a switch having an external contact-type control element carried by a vertically-displaceable assembly which drives and programs the displacements of a transversely displacing transport slide bar. The drive means includes a vertically depending cam carried by the vertically displacing assembly to cause the transport slide bar to move from a primer supply position to a work station where the primer is normally discharged into an area for later assembly with a cartridge or casing. If the transport slide bar fails to displace from the supply position to the work station position as the vertically-displaceable assembly descends, the control element power interrupt switch moves into an interfering relationship with the slide bar, thus, opening a relay between an electrical line, for example, and a motor which acts as the motive power source for the drive means.

The various features and advantages of the invention will become more apparent from a reading of the following description of an illustrative embodiment of the invention. By way of general description, this illustrative embodiment comprises a support surface in the form of a lower platen across which shells, casings, or cartridges move in an incremental fashion between various work stations at which the aforementioned operations are automatically performed. In one of these work stations a primer or percussion cap is caused to be inserted into the cavity at the end of the cartridge shell or casing. These primers are placed in position for assembly by means of a transport member in the form of a flat bar which displaces horizontally and cyclically across the lower platen under the driving force of a motor and an upper platen assembly which moves vertically and cyclically relative to the lower platen to perform many of the machine operations involved in a loading sequence. The upper platen carries a cam having a dog leg profile on at least one surface, this cam interacting with a follower on the transport slide to program the horizontal motion of the slide and to synchronize it with the vertical motion of the upper platen. The slide moves between a first position in which a vertically-oriented receptacle or aperture is lined up with a vertically stacked primer supply, thus, to permit the lower-most primer to drop into the receptacle aperture, and a second position horizontally spaced from the first position wherein the primer receptacle is lined up with a lower platen aperture or seat into which the primer is dropped for later assembly to a cartridge shell or casing. The slide is urged forwardly by a spring which, thus, provides a resilient drive tending to urge the slide follower into constant contact with the cam surface. Thus, only the force of the spring can be exerted on any primer which might be placed in an interfering relationship with the sliding transport member and the spring force is selected to be'less than that which would cause a spontaneous primer explosion. However, the cam follower arrangement is such as to provide a positive drive of the transport slide back toward the supply position. The receptacle-aperture in the slide when in the supply position lines up with a vacuum fitting and an aperture in the lower platen which clears the supply area of excess primer powder which might otherwise build up to potentially explosive portions. In addition, dirt and other foreign particles are kept out of the transport slide receptacle.

The following specification sets forth the illustrative embodiment in full detail and is to be taken with the accompanying drawings of which:

FIG. 1 is a front partial view of an automatic loading machine embodying the invention;

FIG. 2 is a schematic side view of a part of the macine of FIG. 1 in a first position;

FIG. 3 is a schematic side view of a part of the machine of FIG. 1 in a second position;

FIG. 4 is a rear view of another part of the machine of FIG. 1 showing a detail in a first position; and,

FIG. 5 is a rear view of the part from FIG. 4 in a second position.

Referring now to FIG. 1, there is shown an automatic ammunition loading machine comprising a base 11 supporting a lower platen 12 which defines a series of laterally spaced work stations at which various loading operations are progressively performed. A shuttle bar 62 is caused to travel a substantially rectangular path to carry the casings through the work stations in an incremental fashion. The operations performed at each station are subassembly operations to be performed in a certain order. The finished ammunition emerges from a chute 13.

The platen 12 carries guide pins 40 which define the vertical path of travel of an upper platen assembly 38 which when reciprocally, vertically driven, effects several of the loading operations as hereinafter described. One of these operations is the metering of primers from a supply tube 26 to a work station directly in front of the tube 26, an operation best understood by reference to the following description of FIGS. 2 through 5.

Referring now to the FIGS. 2 through 5, there is shown a representative portion of the automatic loading machine 10. Platen 12 is a substantially rectangular steel plate having a shallow groove or channel 14 machined into the upper surface thereof to receive and direct a horizontally displaceable primer transport member comprising a fiat machined steel bar 16 and suitably secured thereto a steel slide block 18. The transport member comprising bar 16 and block 18 operates to individually meter percussiontype primers 24 from a supply represented by hollow vertical tube 26 to a work station which is displaced to the left, as shown in FIG. 2, for example, of the supply, where the primers are assembled into cartridges as one of several steps which are automatically carried out by the machine 10. The transport member comprising bar 16 and block 18 is caused to be displaced horizontally, that is, from left to right in FIG. 2 in a cyclical fashion by drive means to be described.

The slide bar 16 has formed in the forward portion thereof, that is, the portion to the left in the drawing of FIG. 2 a vertically-oriented aperture 20 having a rounded interior peripheral lip 22 to serve as a metering receptacle for primers 24 which are stacked vertically on top of one another in the supply tube 26. The tube 26 is supported by means, not shown, relative to the lower platen 12 so as to provide registration between the discharge opening at the bottom of the tube 26 and the aperture 20 in the slide bar 16 during each cyclical displacement of the slide bar relative to the platen 12. :In the apparatus 10 of FIG. 1, the aperture 20 is aligned with the opening in the primer tube 26 as the slide bar is caused to be traversed to the right-handmost position, this position being illustrated in FIG. 2.

In a specific embodiment, the primers 24 are approximately 0.165 inch in diameter and 0.117 inch in vertical height or thickness. Accordingly, the aperture 20 in the slide bar 16 is made slightly oversize to have a diameter of 0.179 inch and a vertical height or thickness of 0.134 inch. The rounded lip 22 together with the slightly rounded edge configuration of the typical primer 24 provides compensation for the 0.017 difference in the height or thickness of the aperture 20 and primer 24 which, as will be apparent, permits the second primer up in the stack to fall slightly into the aperture 20. As the slide bar 16 is displaced to the left, as shown in FIG. 2, the entire stack of primers 24 is, thus, caused to rise the 0.017 inch necessary to provide clearance for the upper surface of the slide bar 16. In addition, the slight vertical oversize of the aperture 20 in the slide bar 16 compensates for any rough edges or small amounts of particle accumulation which may occur in the primer receptacle defined by the aperture 20, thus, to reduce the possibility of a jam occurring at the primer acceptance position shown in FIG. 2.

The minimization of foreign particle collection is significantly enhanced in the apparatus 10 of FIGS. 2 and 3 by the provision of a vacuum apparatus including a fitting 28 which is threaded into a tapped portion of a vertical channel 30 in the lower platen 12, the fitting being connected to a pipe 32 which in turn is connected to a vacuum pump 34. As shown in FIG. 2, the channel 30 is aligned with the primer supply tube 26 and, thus, when the slide bar 16 is in the primer pick-up position shown in FIG. 2 the channel 30 is also aligned with the aperture 20 in the slide bar 16. Channel 30 is about inch in diameter, too small to permit a primer to fall through. By causing an air flow the supply area to the pump 34, any excess primer powder which is inherently carried by the primers 24 is swept away rather than permitted to accumulate in the primer pick-up area where if present in sufiicient quantity a danger of explosion could result. In addition, the vacuum action clears the primer pick-up area of other foreign particles, such as dirt which might interfere with the proper seating of the primers 24 into the aperture 20 and which could, thus, cause an interruption of automatic loading operation. Finally, the vacuum force tends to draw the lowermost primer 24 into aperture 20, assisting the gravity feed.

From the primer pick-up position shown in FIG. 2 wherein gravity causes the lowermost primer 24 in the supply tube 26 to fall into the aperture 20 in the slide bar 16, the drive means to be described causes the slide bar 16 to move forwardly, that is, to the position illustrated in FIG. 3. This position aligns aperture 20 with a work station defined by a receptacle 36 in the lower platen 12. The drive means is such as to cause the aperture 20 and the slide bar 16 to be in register with the receptacle 36 during each cyclical displacement of the slide bar, thus, to permit the primer 24 being carried forward by the slide bar to fall into the receptacle 36. According to typical machine operation, the slide bar 16 is then drawn back and a shuttle bar 62 captures a cartridge, casing, or shell to be assembled and mechanical means not shown, cause the primer which has been placed in the receptacle 36 to be assembled into the cartridge, casing, or shell in a suitable manner. Typically, this involves the application of a blunt pin upwardly through the small opening which connects with the receptacle 26, as shown in FIGS. 2 and 3.

Describing now the drive means for effecting the cyclical displacement of the slide bar 16 as well as apparatus associated therewith, the machine comprises an upper platen assembly 38 which is mounted on one or more guide pins 40 which in turn are suitably anchored to the lower platen 12. The assembly 38 is, thus, mounted for cyclical vertical displacement to effect various automatic loading operations, such as metering primers, powder and shot, crimping, and so forth. The upper platen assembly 38 is caused to be cyclically vertically displaced by a motor 42 and a suitable crankshaft arrangement, these elements being preferably disposed within base 11. Upper platen assembly 38 carries on the righthand edge thereof, as shown in FIGS. 2 and 3, a depending vertical cam 44 which programs the cyclical horizontal displacements of the slide bar 16 to be synchronized mechanically with the vertical displacements of the upper platen assembly 38. The program surface of cam 44 is on the rear, that is, the righthand edge of the cam, as shown in FIGS. 2 and 3, and includes two vertical portions 46 and 48 joined by an inclined or angulated surface 50. The surface of cam 44 is contacted by a roller-type follower 52 on the slide block 18. The surface portion 46 of cam 44 represents the dwell of the slide bar 16 in the primer discharge position of FIG. 3 wherein aperture 20 is in register with receptacle 36. The surface portion 48 of cam 44 represents the primer pick-up position of slide block 16 wherein the aperture 20 is in register with the supply tube 26 and the vacuum channel 30, as shown in FIG. 2. The inclined surface portion 50 of cam 44 represents the displacement or travel of the slide bar 16 between these two dwell positions.

As is best illustrated in FIGS. 2 and 3, the roller follower 52 contacts only one side of the cam 44, thus, the slide bar 16 and the slide block 18 are positively driven by cam 44 only from the work station defined by receptacle 36 to the supply point defined by the position of the supply tube 26. To drive the slide bar 16 in the oppositedirection, that is, from the supply point to the work station with the primer being carried into place, an anchor block 54 is mounted on the lower platen 12 by suitable fastener means, such as machine screws, and carries a forwardly extending and horizontally oriented guide rod 56 which extends into a deep hole 58 in the slide block 18. A spring 60 is disposed in the hole 58 and about the rod 56 so as to abut against the anchor block 54 to bias the slide block 18 to the left, as shown in FIGS. 2 and 3. This resiliently biases the follower 52 against the program surface of cam 44 such that only the force of the spring 56 actually drives the slide bar 16 from the supply point to the work station. This has the advantage of eliminating any positive machine drive on the slide bar 16 during the travel of the slide bar to the work station, thus, minimizing if not substantially eliminating the possibility of applying the full pressure generated by the force of motor 42 on the slide bar 16 to a primer 24 which may have been caused to occupy an interfering and, thus, jamming relationship with respect to the slide bar 16. For example, it occasionally occurs in the reloading of previously-used ammunition cases that the step of removing the previously-used primer is incomplete and effective only to remove the center of the primer leaving the outer wall thereof in place. This outer wall then occasionally stays in the metering area such that the next primer 24 may be placed into a jammed position. The location of a primer 24 half-way, for example, into the aperture 20 causes a shearing pressure to be applied to that primer when the slide bar 16 begins its forward travel, the primer being squeezed between the rear surface of the aperture 20 and the front inner surface of the supply tube 26. Under these circumstances, the explosion of the single primer is quite possibly effective to discharge all of the primers stacked up vertically in the supply tube 26, thus, causing an explosion of possibly lethal proportions. The spring 60, thus, produces a resilient, rather than positive, drive of the slide block 16 toward the work station, the tension of the spring being selected to be substantially less than that which can trigger a primer under ordinary circumstances. The positive drive of the slide bar 16 from the work station back to the slide point is satisfactory since, at this point, no primer can occupy an interfering and, thus, jamming position in the machine 10.

The machine 10 comprises an additional control means for interrupting the application of electrical energy to the motive power source 42 in the event the slide bar 16 and the slide block 18 associated therewith fails to traverse forwardly, that is, to the left as shown in FIGS. 2 and 3 as the upper platen assembly 38 descends. Such an occurrence is indicative of a jam in the primer metering apparatus and, thus, causes a temporary shutdown of the automatic loading operation.

This control means is illustrated in FIGS. 2 through 5 and includes a mechanically operated switch 64 which is mounted on the upper platen assembly 38 by means of a bracket 66 such that the switch 64 is vertically and cyclically displaced along with the upper platen assembly 38. Switch 64 may be of the type commonly identified as a Microswitch and is provided with a rotatable control element 68 which is biased downwardly such that the switch 64 resides in a normally-closed condition. However, control element 68 is angularly displaceable by an externally-applied force to open the switch 64. Switch 64 is in turn connected to a relay 70 which constitutes the main conductance path between the volt AC supply and the motor 42.

Switch 64 is mounted on the back of the upper platen assembly 38, as shown in FIGS. 2 and 3, and vertically above the righthand end of the slide block 18, as shown in FIGS. 4 and 5. Accordingly, a straight vertical displacement of the upper platen assembly 38 and the switch 64, as is required by the guide pins 40, displaces the control element 68 along a path which intersects the path of occupancy of the control block 18 during its cyclical displacement. However, if the spring 60 is effective to bias the roller follower 52 against the program surface of cam 44, the inclined area 50 permits the slide block 18 to move out of the way of the control element 68 as the upper platen assembly 38 descends. Thus, under normal operating conditions the control element 68 remains downwardly biased. The switch 64 remains closed; the relay 70 remains closed; and power is continuously applied to the motor 42 to continue the automatic loading operation.

However, if a primer jam occurs in such a fashion as to prevent the forward displacement, that is, from right to left, as shown in FIGS. 2 and 3, of the slide bar 16 and the slide block 18 which is secured thereto, the downward displacement of the upper platen assembly 38 carries the control element 68 of switch 64 directly into the area occupied by the slide block 18 as shown in FIG. 5. This torques the control element '68, opening the switch 64 and, in turn, opening relay 70. This interrupts the conductance of electrical energy to the motor 42 shutting down the operation of machine 10 until the jam condition has been cleared up and the relay 70 reset. A manual bypass for relay 70 may be included so that the motor 42 can be advanced in small increments after the jammed condition has been cleared up or in the process of clearing up the primer jam. In the machine art, this is known as a jog and will not be described in detail.

In summary, it has been demonstrated that an automatic loading machine for ammunition may be provided with a cyclically translating transport member for metering primers between a supply area and a work station, the drive means for this transport member being such as to provide a resilient, relatively low force drive from the supply to the work station and a positive relatively high force drive from the work station back to the supply. This has the advantage of decreasing, if not eliminating the likelihood of inadvertent and spurious detonation of a pressure-sensitive primer while undergoing automatic loading in the machine. In addition, the likelihood of such spurious detonation is further reduced by means of a vacuum cleaning arrangement which clears the metering receptacle in the slide bar. Finally, an interruption of the application of power to the motive power source of the machine is caused in the event the primer transport mechanism is found to be out of displacement synchronism with the drive means or with a machine part with which it normally displaces in synchronism.

It is to be understood that the foregoing description is illustrative in nature and is not to be construed in a limiting sense.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Primer transport apparatus for loading machines comprising: support means, a transport member displaceable relative to the support means for cyclically transporting primers from a primer supply to a work station, drive means for resiliently urging the transport member toward the work station but positively driving the member from the work station back toward the supply, and means responsive to a failure of said transport member to move away from said primer supply for shutting 01f said drive means.

2. Apparatus as defined in claim 1 wherein the transport member includes a portion defining a primer receptacle which is placed in communication with the supply during each cylical displacement of the member to receive a single primer therein.

3. Apparatus as defined in claim 2 wherein the trans port member includes a flat bar of rigid material displaceable across and in contact with the support means, the receptacle defining a vertically extending aperture in the bar of a depth slightly greater than the depth of a primer and having a rounded peripheral tip.

4. Apparatus as defined in claim 2 including a supply tube disposed over the transport member for containing a vertically stacked array of primers, the tube having an open discharge aperture which is in register with the receptacle during each cyclical displacement of the member.

5. Apparatus as defined in claim 1 wherein the drive means comprises anchor means on the support means, a displaceable cam for programming the displacement of the transport member relative to the support means, spring means for resiliently biasing the transport member against the cam and relative to the anchor means during travel of the member toward the work station, and follower means on the member and engaging the cam for positively driving the member away from the work station.

6. Apparatus as defined in claim 5 including an upper platen vertically displaceable relative to the support means, the cam being carried by the upper platen for displacement therewith.

7. Apparatus as defined in claim 6 wherein the cam has thereon a surface having first and second vertical portions representing dwells of the transport member at the supply and work station respectively, and an inclined portion joining the first and second portions for causing displacement of the transport member.

8. Apparatus as defined in claim 7 including a follower on the member, the drive means including a spring for resiliently biasing the follower against the surface to provide the cyclical displacement of the member.

9. Apparatus as defined in claim 1 including a motive power source for the drive means, said means responsive to failure of said transport member to move including control means for interrupting the operation of the source whenever the transport member fails to move toward the work station under the resilient urging of said drive means.

10. Apparatus as defined in claim 9 wherein the transport member includes a bar slideably displaceable over the support means, and the drive means includes a cyclically, vertically displaceable assembly, a cam carried by the assembly for synchronizing the displacement of the bar therewith, a follower on the bar and a spring biasing the follower against the cam, the control means comprising a switch carried by the assembly and having a control element for controlling the electrical condition thereof, the control element being disposed to contact the transport member only if the bar fails to slide to the work station as the assembly descends.

11. Apparatus as defined in claim 1 including a primer receptacle in the transport member, and vacuum means for exerting a pneumatic force tending to draw primers into the receptacle and to clear the receptacle of foreign matter.

12. Apparatus as defined in claim 11 wherein the vacuum means includes an aperture in the support means in vertical register with the supply, a vacuum pump in communication with the aperture such that as the receptacle of the transport member lines up between the aperture and the supply, a primer is drawn into the receptacle by said pneumatic force, the aperture being of such size as to prevent passage therethrough of a primer.

References Cited UNITED STATES PATENTS 3,036,488 5/1962 Bihler 8626 3,580,128 5/1971 Leich 8631 3,153,976 10/1964 Linder 8626 3,253,496 5/1966 Beach et al. 8626 3,057,247 10/ 1962 Behrens 8631 2,829,553 4/1958 Twidwell 8623 X 3,157,086 11/1964 Bachhuber 8631 X 472,990 4/ 1892 Gallup 8625 BENJAMIN A. BO'RCHELT, Primary Examiner H. TUDOR, Assistant Examiner US. Cl. X.R. 8620

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