Patented Oct. 1, 1946 2,408,475 U'NlTED STATES „PATEN 'r _OFFICE ' ’ 27,468,476 CUTTER CHAIN v Charles F. Osgood,` Claremont, N. H., assigner to> Joy Manufacturing Qoçmpany, a corporation of Pennsylvania 1 Application March 23, 1942, >serial No. 435,805 7 Claims. (ci. 2762-33) . This invention relates to cutter chains and more particularly to improvements in holders for cutter bits especially designed for use with the .cutter chain of a coal mining machine. „ In mining machine cutter chains, it is a Well ., known practice to provide a bit holder having a shank received in the right angle socket of a are set forth, reference for the purpose being hadv to theaccompanying drawing, in which: Fig. 1 is a fragmentary side elevational View of a cutter chain havinga preferred illustrative form of the improved bit holding means associated therewith. ` l Fig. 2 is a front end elevational view of the conventional chain block, and secured in position cutter chain shown in Fig. 1, With the strapslinks on the block by a conventional set screw. With in> cross section. many such holders the set screw not only serves -10 Fig. v3 is a fragmentary viewin longitudinal tc secure the holder shank in the block Socket, vertical section taken substantially on line 3-3 „but also to secure the cutter bit on the holder. of Fig. 2. » Y . With such a construction, in the event the set .Fig..4 is a detail sectional view taken on line .screw becomes loose during Vthe cutting oper @-4 of Fig. 3. . ation, the cutter bit is not only released from the Y Fig, 5 is a perspective view of the cutter bit. Aholder but also the holder is released from the ' Fig. G is ar’perspective view of the improved block. ` ` . bit clamp. ~ ’ . . i it is the purpose oi the present invention to _provide a novel bit holding means wherein the Fig. 7 is a perspective view of the bit holder. Fig. 8 is .a fragmentary sectional View taken on . rins for securing the holder on the Vchain _block 20 the planel of. Fig. 3, illustrating a, modiñed :form separate and distinct from the means for se of- the invention, parts being shown in full to curing the cutter bit on the holder. With such facilitate illustration. „ an improved construction, it is possible to free In both illustrative embodiments of the inven the cutter bit from the holder without disturb tion, the improved bitholding means is shown t-he relation of the holder- with respect to> associated with a chain block cfa conventional the chain block. This not only enables rapid' cutter chain. It will be'v evident, however,- that eas;7 reversal >and replacement of a worn cut the invention may be associated with cutter ter bit but also prevents the release of the holder from the block in the event the securing _means for thel cutter bit for any reason becomes loose. Fur- , ther, in such a novel construction the holder _may be attached to a chain block of a conventional cutter chain without any change in thel parts, and the conventional set screws of the block may serve to hold the cutter bit and holder in posi tion. This not only simpliñes the structure of the holder, but also facilitates the attachment of lthe holder to the chain block. chains of other types. , ` l lThe cutter chain disclosed herein comprises >a chain block I pivotally connected at 2 -to strap links 3. The- chain block has a lateral lug 4 formed witha conventional right .angle socket 5 oi generally rectangular cross section. The chain block lug t has .front and rear threaded open ings 6, t for the reception of vconventional set screws l, l respectively. In the prefered illustrative embodiment of the invention shown in Figs. 1 to 7 inclusive, the im l An object of the present invention is to provide proved bit holding means comprises a holder S `a novel cutter chain. Another object is, to provide 40 having a head Sand an integral shank Iii, the improved cutter bit holding meansfor a cut latter receivable in the chain block socket 5. The chain. Yet another object is to provide im holder head has a plane inner surface il which proved means for securing a cutter bit to the holder. A further object is to provide novel means rests on the outer surface I2 of the chain block lug The holder head is formed with an ob for attaching a conventional cutter bit to the chain block of a conventional cutter chain. A still further object is to provide an improved cut ter bit holding means wherein the means for se liquely disposed bit receiving socket I3 for the reception ofacutt'er bit i4. The cutter bit, which curing the cutter bit to the holder is separate "and distinct from the means for securing the holder to the chain block. How these and other obâects are accomplished, and the advantageous holder head is shaped to conform to the shape of the cutter bit._.`The, cutter bit has oppositely is oi a conventionaldesign, is- generally diamond shaped in cross section and the socket I3 in the disposed, relatively inclined, elongated plane cut ting faces i5, i5 lying in the sides of a triangle features of the invention, will be best understood and terminating rin cutting points I6, i6 atthe 'from the following detailed description wherein opposite extremities of the bit. In this construc >preferred and modiñed illustrative embodiments 55 tion, secured within the holder head 9 and trav 2,408,476 4 clamp I8 by means of the rear set screw 1 for wardly relative to the holder and chain block so as to release the surface 24 of the front bit stop I1 from engagement with the cutter bit. received in the front set screw opening 6 in the chain block lug, is adjustable to engage the shank 6 When the front bit stop I1 is in its foremost re ersing the blt receiving socket I3 is an abutment pin I6' against which the inner inactive cutting face I5 of the cutter bit rests. The set screw 1, IE! of the holder for securing the holder in posi tion on the chain block with the surface I I on the leased position, the cutter bit may be withdrawn forwardly from the holder head socket I3 with out disturbing the relation of the holder with holder head resting against the exterior surface respect to the chain block. It is accordingly evi I2 of the chain block lug. Engaging the inner portion of the active front cutting face I5 of the 10 dent that even if the rear set screw 1 becomes slightly loosened so that the clamp is free to cutter bit is a front stop I1 of an adjustable move forwardly to permit bit release, the holder clamp I8. This clamp has an elongated central shank I0 will still be firmly held in position within opening I9 which receives the inner portion of the socket of the chain block by the front set the holder head, and the latter has lateral ledges ZI), 2i) which overlie the sides of the clamp in the 15 screw. Thus the clamp may be released to per mit reversal or replacement of the cutter bit manner shown in Fig. 4, so that the clamp strad quickly and with facility without disturbing the dles the holder in the manner shown. Thus the holder at all. holder maintains the bit clamp in position on In the modified embodiment of the invention the block. The clamp has at its rearward end _a downwardly bent portion 2I which is slotted at 20 shown in Fig. 8, the holder and clamp are oper 22 to engage the annular grove 23 of the rear set screw 1. The front stop I'I of the clamp has a rearwardly facing, inclined surface 24 against which the forward face of the cutter bit rests, and the active cutting point of the cutter bit 25 projects outwardly and forwardly with respect to the holder and clamp in the manner shown in ated in a manner similar to that above described. In this instance, however, instead _of engaging the clamp with the rearset screw of the chain block for adjustment by the same; adjustment of the clamp is effected by engagement of the set screw 21 with the projection 28 integral with the holder head. This construction is particularli7 advantageous when the bit holding means is Fig. 3. associated with a cutter chain wherein but one set In the modified embodiment of the invention shown in Fig. 8 the clamp I8' has an upwardly 30 screw opening, i. e. the front one, is provided on the chain block lug. Otherwise, the manner of bent portion 25 provided with a threaded opening use of this form of the invention is similar to 2B for the reception of a set screw 21. The holder that above described. 9' is similar to the holder 8 above described eX As a result of this invention, it will be noted cept, in this instance, the rearward portion of the holder head is formed with a projection 2S 35 that an improved cutter bit holding means is pro vided whereby a cutter bit may be firmly secured' against which the set screw 21 is adapted to abut. in position on a chain block of a conventional It is accordingly evident that the bit clamp, in cutter chain. It will further be evident that by stead of engaging the rear set screw of the chain the provision of the bit clamp having adjusting block as in the preferred embodiment of the in vention, carries a separate set screw which abuts 40 means separate and distinct from the securing means for the holder, the cutter bit may be re the rear surface of the holder head for adjusting leased for reversal or replacement quickly and the clamp with respect to the holder. Otherwise, with facility. It will also be evident that by this form of the invention is similar`to the pre vthe provision of the bit clamping means separate ferred embodiment above described. During assembling of the parts, the holder 45 and distinct from the securing means of the bit holder, the latter will be firmly held in position shank IQ is inserted through the opening I9 in the on the chain block even when the bit securing bit clamp, and the holder shank is then inserted means for any reason becomes loose. The bit within the chain block socket 5 into the position holder and its associated clamp are also simple shown in Fig. 3. with the bit clamp engaging the outer block lug surface. The front set screw 'I is 50 and rugged in design. Other uses and advan tages of the invention will be clearly apparent to then adjusted to engage the holder shank ID those skilled in the art. firmly to secure the holder on the chain block While there are in this application specifically with the inner surface II of the holder head described preferred and modified embodiments resting iirmly against the exterior surface I2 of the chain block lug. The cutter bit may then be 55 which the invention may assume in practice, it will be understood that these embodiments of the inserted past the front stop I1 of the then re same are shown for purposes of illustration and leased clamp, into the socket I3 of the holder that the invention may be further modiñed and head with the inner inactive cutting face I5 of embodied in various other forms without depart the cutter bit resting against the abutment pin I E’. When the cutter bit is in the position shown 60 ing from its spirit or the scope of the appended in Fig. 3, the rear set screw 'I may be adjusted claims. What I claim as new and desire to secure by to move the clamp I8 rearwardly with respect to the holder and chain block to bring the surface Letters Patent is: 1. In a cutter chain, a chain blo-ck having a 24 on the front bit stop I1 in engagement with F the inner portion of the active cutting face I5 60 socket, a bit holder having a shank receivable in the socket of said block, a bit clamp cooper of the cutter bit, thereby to clamp the cutter ating with said holder and having a longitudi bit firmly in cutting position on the holder nally extending portion resting on an outer sur head. The clamp I3 is held in position between face .of said block when the clamp is in operative the ledges 20 on the holder head and the eX terior surface of the chain block lug, the parts be 70 position, said holder having side portions en» gaging the sides of the longitudinally extending ing so formed as to permit free adjustment of portion of said clamp for holding said clamp the clamp relative to the holder while preventing against said block surface and for guiding the any appreciable amount of looseness. When it latter during adjustment thereof relative to said is desired to release the'cutter bit from the holder, this may be accomplished simply by adjusting the 75 holder and said block in a direction lengthwise 2,408,476 5 6 of said block, means for securing said holder on said block, means separate from said securing means for adjusting said bit clamp longitudinally into bit clamping position relative to said holder said holder and said block cooperating to pro vide means extending lengthwise of said block for guiding said clamp, and said opening being and said block, and a cutter bit mounted on said holder and engageable by said bit clamp. 2. The combination with a chain block having a right angle socket and front and rear set screw openings for the reception of set screws and hav elongated in the direction of said guiding means to permit adjustment of said clamp relative to said holder. 5. The combination with a chain block having a socket, of a holder having a head and a shank, said shank receivable in said block socket, means ing set screws in said openings, of bit holding 10 carried by said block for securing said holder means for securing a cutter bit in-cutting posi shank in said block socket, a bit clamp cooper tion on said block including a holder having a ating with said :block and holder, said clamp having an opening for receiving the inner portion head and a shank, said shank receivable in said block socket and the front set screw engageable of said holder head and the latter engaging said with said shank for holding the latter in said 15 clamp to hold the same against said block, and the holder cooperating with said block to provide socket, and a bit stop-providing member co operating with said holder and engageable by , a guidevvay for said clamp between said holder said rear set screw and adjustable by the latter head and the outer surface of said block, said into bit securing position relative to said holder guideway extending lengthwise of said block, and and said block, said holder and said block pro 20 means separate from said shank securing means viding guiding means extending lengthwise of for adjusting said bit clamp along said guideway said block for guiding said stop-providing mem into bit clamping position relative to said holder ber during adjustment thereof. and said block. 6. -The combination with a chain block having 3. The combination with a chain block having a right angle socket and front and rear set screw 25 a socket, of a bit holder having a head and a openings for the reception of set screws and shank, said shank receivable in said block socket, having set screws in said openings, of bit hold means carried by said block for securing said ing lmeans for securing a cutter bit in cutting holder shank in said block socket, an adjustable position on said block including a holder having bit clamp arranged between and guided vby said a head and a shank, said shank receivable in said 30 holder and block, said holder head engaging said block socket and the front set screw engageable clamp to hold the latter in operative position. with said shank for holding the latter in said against the block and said holder and the block socket, and a bit stop-providing member cooper cooperating to provide guiding means for the ating with said holder and engageable by said clamp extending lengthwise of the block, and rear set screw and adjustable by the latter into bit securing position relative to said holder and means separate from said shank securing means for adjusting said bit clamp into bit clam-ping position relative to said holder and said block. an opening> for receiving said holder head and '7. The combination with a chain block having the latter cooperating with said block to pro a right angle socket and adjustable devices ar vide a guide for said stop-providing member ranged on said block respectively forwardly and during adjustment of the latter, said guide ex rearwardly of said socket, of bit holding means tending lengthwise of said block, and said open for securing a cutter bit in cutting position on ing being elongated in the direction of said guide said block including a holder having a head to permit adjustment of said stop-providing and a shank, said shank receivable in said block member relative to said holder. ` 45 socket and said front device engageable with 4. The combination With a chain block having said shank for holding the latter in said socket, a socket, of a holder having a head and a shank,> and a bit-stop-p-roviding member cooperating said shank receivable in said block socket, means with said holder and engageable by said rear carried by said block for securing said holder device and adjustable by the latter into bit secur shank in said block socket, a bit clamp cooper 50 ing position relative to said holder and said ating with said block and holder, said clamp hav block, said holder and said block cooperating to ing an opening for receiving the inner portion provide guiding means extending lengthwise of of said holder head and the latter engaging said said block »for guiding said stop-providing mem said block, said stop-providing member having clamp to hold the same yagainst said block, and ber during adjustment thereof into’bit clamping means separate from said shank securing means 55 position. for adjusting said bit clamp into bit clamping position relative to said holder and said block, . yCHARLES F. OSGOOD. '