US 3273777 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
Sept 20, 1966 A. G. JulLFs ETAL EASY CLEAR GUIDE BODY 2 Sheets-Sheet l Filed March ll. 1964 INVENTORS ALerz-r G. dum-'5,
GEORGE C.Juu.1Fs AND CARL T. BEcHT, 7mm
Sept 20, 1966 A. G. JulLFs ETAL EASY CLEAR GUIDE BODY 2 sheets-smet 2 Filed March ll, 1964 INVENTORS A F MS ufff WUH du GCB TEL am.. www n AGCL W J QU..
United States Patent O 3,273,777 EASY CLEAR GUIDE BODY Albert G. Juilfs, George C. Juilfs, and Carl T. Becht, all of Cincinnati, Ohio, assignors to Senco Products, Inc., Cincinnati, Ohio, a corporation of Ohio Filed Mar. 11, 1964, Ser. No. 351,027 6 Claims. (Cl. 227-123) This invention relates to yfastening devices and fastener driving, and more particularly to an improved guide body designed to be automatically opened should a fastener jam occur, whereby normal cycling of the tool will clear the jam.
Fastener driving tools of all kinds generally include a driver, a drive track, means for reciprocating the driver in the drive track, and means for successively feeding a plurality of fasteners into the drive track in a position to be driven into a workpiece by the driver. The drive track, in cross section, is designed to closely accommodate a single fastener, and of course, serves to guide that fastener during the driving operation. A jam occurs when for some reason, a fastener gets deformed within this drive track, often causing the driver to become wedged between the deformed fastener and the walls of the drive track which will often result in deformation of the driver and/or the occurrence of undue stress on the guide body and related components. While such a jam can occur in any type of fastening device, it is particularly critical in the case of a large, pneumatic fastening device wherein the driver is forced downwardly by relatively large forces, thereby tightly wedging itself in the drive track.
It will of course be understood that because of the narrow confines of the drive track, it is extremely dithcult to clear a jam in a conventional fastening device. In many cases, it can only be cleared by disassembling the guide body. This is of course a time consu-ming operation, and materially cuts down on the productivity of the operator.
The prior art has devised a number of guide body constructions including a normally closed gate or nose piece which may be manually opened, thereby giving access to the drive track to permit removal of the jammed fastener. These prior devices have been commercially unsuccessful for various reasons.
In the rst place, certain of these devices are characteriz/ed by a latch which must be moved rearwardly in order to open the nose piece; however, the presence of a deformed fastener and/ or driver in the drive track under jammed conditions makes it extremely difficult to move the latch means rearwardly, and hence makes the opening operation extremely diicult.
Secondly, in the great bulk of these prior art devices, the fasteners are urged by the magazine or other feeding means against the movable nose piece or gate. As will be immediately recognized by the skilled worker in the art, this makes it very difficult to accurately -position a fastener in the drive track under the driver, and may in fact cause jams to occur more often.
It is therefore a general object of this invention to provide an improved guide body which obviates the above noted disadvantages.
More specifically, it is an object of this invention to provide an improved guide body which is automatically opened upon the occurrence of a jam. This of course means that the fastening device may be cleared by repeating its normal cycle of operation.
Still another object of this invention is` an improved guide body wherein the automatic opening of the nose piece is occasioned by the extra-ordinary pressure of a jammed fastener in the drive track.
A very important object of the invention is to provide an arrangement which will serve as an overload release ICC whereby to prevent damage to the driver, guide body, fastener feed magazine, nad the various connecting componente.
A :further object of the invention is the provision of an improved guide body which includes a positive, xed, feed stop. This of course insures accurate positioning of the fastener in the drive track, and insures that the occurrence of jams is kept at a minimal level.
Various other objects and advantages of this invention will become apparent to the skilled worker in the art upon rea-ding the following specification in conjunction with the attached drawings. The drawings illustrate several embodiments of the invention, and in so far as it is possible, similar refe-rence numerals have been used to designate like parts throughout the several views.
FIGURE 1 is a front elevational view with parts in section of the improved guide body of this invention applied to a pneumatic stapling device;
FIGURE 2 is a cross sectional view of the embodiment shown in FIGURE 1, taken along the line 2-2 thereof;
FIGURE 3 is another cross sectional view of the embodiment shown in FIGURE 1, taken along the line 3-3 thereof;
FIGURE 4 is a front elevational view with parts in section of another embodiment -of this invention;
FIGURE 5 is a side elevational view of the embodiment shown in FIGURE 4;
FIGURE 6 is a side elevational view with parts in section of still another embodiment of this invention;
FIGURE 7 is another view of the embodiment shown in FIGURE 6, as seen from the bottom with the gate or nose piece in the opened position;
FIGURE 8 is a side elevational view of still another embodiment of this invention; and
FIGURE 9 is a bottom plan View of the embodiment shown in FIGURE 8.
It will be understood that FIGURES 4 through 9 show the improved guide body of this invention as separate land apart from a fastening device; and while FIGURES 1 through 3 sholw the improved guide body of this invention as applied to a pneumatic stapler, no limitation is intended thereby. The guide body of this invention may be advantageously utilized in conjunction with any and all fastening devices. Accordingly, the term stapler is used hereinafter to designate generically `all the devices to which the improved guide body of this invention is applicable.
Briefly considered, the improved guide body of this invention is adapted to :be secured to a conventional stapler including a staple driver, means for reciprocating the staple driver, and means for successively feeding a plurality of staples into the drive track in the guide body in a position to be driven by the staple driver. The guide body itself includes a fixed body portion fixed to the stapler, a positive staple feed stop associated with the xed body portion, and a nose piece hingedly secured to the fixed body portion. This nose piece is movable from a closed position, wherein it denes a portion at least `of one `wall of the staple drive track, to an open position, the open position of the nose piece providing free access to the drive track. The movable nose piece described above is releasably held in the closed position by the coaction of a pair of cam surfaces, one of these cam surfaces being normally biased by a suitable resilient means.
Upon the occurrence of a jam in the staple drive track, it will be apparent that extra-ordinary forces will be exerted against the walls of the drive track. The cam surfaces and resilient means described above will be so arranged that this condition serves to overcome the biasing action of the resilient means and automatically opens the hinged nose piece. As indicated above, this will completely open the staple drive track, and permit ready clearance of the jam by completing or repeating the normal operative cycle of the tool and/or by providing easy access to the ydrive track.
Referring now to FIGURES 1 through 3, the improved guide body of this invention is shown as applied to a pneumatic stapler including a working cylinder 10. It will of course be understood that the cylinder accommodates a working piston (not shown) which may be reciprocated in any well known and conventional manner, as 4for example by air, springs, or a combination `of air and springs. The guide body indicated generally at 11 is secured to the lower end of the cylinder 1t), and includes a staple drive track 12. At is also conventional in the art, the stapler shown includes a magazine 13, which serves to successively feed a plurality of staples 14 into the drive track 12, in a position to be driven by the staple driver 15, which it will be understood is actuated by the piston or other working member in the cylinder 10.
The guide body 11 of this invention includes a body portion 16, which is formed in a suitable manner to provide the rear and side walls of the drive track 12. As best seen in FIGURES l and 3, the lfront of the body portion 16 is provided with a slot 17 which is somewhat Wider than the staple drive track, and extends from the bottom of the guide body upwardly to a point slightly higher than the top of a staple 14 positioned in the drive track 12 ready for driving.
Hingedly secured to the body portion 16 by means of a pin 18 is the movable, normally closed nose piece 19. As is clearly apparent from the drawings, this nose piece 19 is movable from a closed position wherein it is received in the slot 17, thereby forming at least a portion of one wall of the drive track 12, to an open position, wherein the lower .portion of the drive track is readily accessible. By lower portion of the drive track it is of course meant that portion of the drive track extending from the point where the staples are introduced by the feeding mechanism, down to its open bottom.
In the devices of the prior art, the staples under the urging of a suitable feeding means are forced against the front Wall of the drive track (which is also the movable gate or nose piece), and this is the sole means by which staples are successively positioned in the drive track. It is readily apparent that under such circumstances, the quality of t between the nose piece 19 and the body portion 16 is of critical importance, in insuring accurate positioning of the staple in the drive track. That is, if the nose piece 19, through wear, developed a bit of play in its t, staples fed thereagainst would no longer be accurately positioned in the `drive track with respect to the staple driver. Therefore, it is a very important feature of this invention to provide a fixed, positive staple feed stop.
This is accomplished in the instant invention by means of an abutment 20. As shown in the drawings, this abutment -or staple feed stop 20 is located vin the path of a staple being introduced into the drive track. In other words, this abutment 20 in effect forms a stationary, fixed portion of the -front wall of the staple drive track 12. Thus, during all times the fastening device is in operation, the feed stop 20 is a rigid, immovable part of such drive track 12. This insures that the staples are accurately and precisely located in the track as they issue from the feed means and abut this stop 20.
This construction provides one `further important advantage. Namely, were such a staple feed stop not provided, all of the staples in the magazine would be ejected from the stapler upon opening of the nose piece 19. By virtue of the abutment or stop 20, however, staples in the magazine are fed to their normal position, and stopped, even though nose piece 19 is opened.
The foregoing elements of the guide body of this invention are common to all embodiments shown hereinafter, and accordingly, similar reference numerals will be used to designate corresponding parts in the remaining embodiments.
In the embodiment shown in FIGURES 1 through 3, the means for releasably holding the nose piece in its closed position comprises the detent buttons 21 and 22, normally urged outwardly by the spring 23. The detents 21 and 22 are eac-h provided with the annular recess 24, so that the pins 25 and 26 respectively serve to retain them in the nose piece.
In the normally closed position, the detents 21 and 22 are engaged in the curved recesses 27 and 28 respectively, formed in the side walls of the slot 17 of the body portion 16.
As best seen in FIGURE 3, the mating sur-faces of the detents 21 and 22 and the recesses 27 and 28 respectively are sloped, thereby providing a pair of coacting cam surfaces. Due to the urging of the spring 23, the coacting surfaces described above tend to urge the nose piece 19 toward its seat in the body portion 16. However, the presence of extra-ordinary forces in the drive track, such as would be occasioned upon the occurrence of a staple jam, will overcome the bias of the spring 23 forcing the detents 21 and 22 inwardly, and permitting the nose piece 19 to swingr outwardly and upwardly, opening the drive track 12. It will then be apparent that normal cycling of the tool will usually serve to clear the jam. The nose piece 19 may easily `be returned to its closed position, and the staple operator can continue at his job wit-hout a significant loss of time.
The arrangement among the detents 21 and 22, cam recesses 27 and 2S, pins 25 and 26, annular recesses 24 and spring 23 is such Ias to compensate automatically for wear. As seen in FIGURE 3 the slope or angle on the ends of the detents 21 and 22 is substantially the same as that of the cam surfaces of the recesses 27 and 28 which they engage. The detents do not bottom in these recesses. Also, -as seen in FIGURES 1 and 3, the pins 25 and 26 are located intermedi-ate the -annular recesses 24. Thus, as wear occurs between the detents 21, 22 and cam recesses 27, 28 the spring 23 simply urges the detents -outwardly to compensate for such wear, as permitted by the extra depth of the recesses 27, 28 and the width of the annular recesses 24, the shoulders ofthe detents 21, 22 normally being out of contact with the pins 25 and 26 (see FIGURE 1).
In the embodiment shown in FIGURES 4 and 5, the movable nose piece 19 is somewhat larger than in the foregoing embodiment Iincluding the side portions 19a and 1912. It will of course be understood that the Ibody portion 16 and slot 17 therein are modified as shown in the drawings to accommodate the nose piece 19-19a-19b.
The portions 19a and 19h of the nose piece are each bored and counterbored to provide the recesses 30 having the shoulders 31. yReceived within these recesses -are the detents 32 and springs 33. The ends of the detents 32 are sloped, and mate with the V shaped grooves 34 formed in the lbody portion 16. As in the foregoing embodiment, these coating cam surfaces normally urge the nose piece 19 to the closed position; however, extra-ordinary forces within the drive tra-ck will be sufficient tto overcome the biasing action of the springs 33, thereby forcing the nose piece 19 open.
Still another arrangement for releaseably holding the nose piece 19 in the closed position is shown in FIGURES 6 and 7. In this arrangement, the rear surface of the nose piece 19 is recessed as at 4t) to accommodate the spring clips 41 held in place in any suitable manner, as by the pins 42. The body portion 16 is provided with the snap buttons 43, which engage the springs 41 and tend to hold the nose piece 19 Iin the closed position. In this embodiment, it will be understood that the spring 41 itself serves as one of the 'coating cam surfaces. The other surface is of c-ourse the groove 44 in the button 43. Operation of this arrangement is in all respects lidentical to that described a'bove.
Still a further arrangement for releaseably holding the nose piece in the closed position is shown in FIGURES 8 `and 9. In this case, the nose piece 19 is provided with the strip `spring 50, formed as illustrated in FIGURE 9. This spring may be secured to the nose piece in any convenient manner, as by the fastening 51. As seen in FIG- URE 9, it will be apparent that the edges of the spring 50 are engaged in the V slots 52 formed in the side edges of the body portion 16. Once again, in this embodiment, the spring 50 itself serves as one of the coating cam surfaces, which along with the slot 52, functions in the manner already described in this specification.
By way of review, it will noted that all of the foregoing described embodiments of arrangements for -releaseably securing the nose piece 19 in its normally closed position include a pair of coacting cam surfaces, and a spring normally biasing one of these cam surfaces. The precise shape of the cam surfaces, and magnitude of the spring are not critical, and may be varied within wide limits, so long as they serve to hold the nose piece closed against ordinary forces occuring in the staple drive track during the driving operation, yet still permit the nose piece 19 to be opened upon the occurrence of an eXtra-ordinary or abnormal force in the drive track.
And it should further be noted by way of review that a very important facet of this invention is the relationship among the body portion 16, movable nose piece 19, and fastener feed stop 20. Thus, as fasteners are fed into that portion of the drive track 12 which passes through the body portion 16 they will engage the feed stop 20 which is, in effect, a permanent part of the `front wall of the drive track 12; it does not swing lout of the way. The nose piece 19, however, which also constitutes a part of the front wall of the drive track 12, will swing out of the way under conditions of pressure bulid-up, whereby to relieve jam conditions and expose the track. In this manner a stop 20 is provided for the fasteners in such a manner that they are accurately positioned in the drive track 12 each time-there is no movement of the stop 20 which can get out of adjustment-and yet a major portion of the track 12 may move so as to relieve pressures within the track and fastening device as may be required from time to time.
It is believed that the foregoing constitutes a full and complete disclosure of the principals of this invention. It will be understood of course, that many modification can be made by the skilled Worker in the ant without departing from its scope and spirit. And while the invention has been shown and described `as embodied in certain particular and specific structures and arrangements, the invention is not to vbe limited to such structures and arrangements except in so far as they are Specifically set forth in the subjoined claims.
What is claimed as new, and what it is desired to secure by Letters Patent is:
1. In a fastening device including a drive track, a
driver, means for reciprocating said driver in said drive track, and means for successively feeding a plurality of fasteners into position to be driven by said driver; an improved guide body comprising:
(a) A body portion defining at least one wall of said drive track;
(b) Fastener feed stop means in fixed association with said body portion, said fastener feed stop means comprising a depending abutment centrally located with respect to said drive track;
(c) A nose piece hingedly secured to the fastening device and movable from a closed position defining at least a portion of another `wall of said drive track lto an open position permitting expulsion of a partially driven fastener through said wall of said drive track; and
(d) Means releaseably holding said nose piece in said closed position.
2. The guide body claimed in claim 1 `where said body portion defines ythe rear and side walls of said drive track.
3. The guide body claimed in claim 1, wherein said means releasably holding said nose piece in said closed position comprises resilient means, said resilient neans being disposed within a recess in said nose piece, and coacting cam surfaces associated respectively with said nose piece and said body portion, said cam surface associated with said nose piece being normally biased by said resilient means into engagement with the other of said cam surfaces, whereby eXtra-ordinary pressure in said drive track is able to overcome said bias and open said nose piece.
4. The guide body claimed in claim 2 wherein said means releasably holding said nose piece in said closed position comprises resilient means and coacting cam surfaces associated respectively with said nose piece and said body portion and wherein a portion of said resilient means itself acts as one of said coacting cam surfaces.
5. The guide body claimed in claim 4 wherein said resilient means is associated with said nose piece, and the other of said cam surfaces comprises a groove in said body portion.
6. The guide body claimed in claim 1 wherein said nose piece is hingedly associated with said fixed fastener feed stop means.
References Cited by the Examiner UNITED STATES PATENTS 1,962,874 `6/1934 Polzer 227-123 1,994,567 3/1935 Gavanagh 227-123 2,775,764 l/1957 Maynard 227-123 GRANVILLE Y. CUSTER, JR., Primary Examiner.