US2730730A

US2730730A - Slotting machine for mine rods

Info

Publication number: US2730730A
Authority: US
Publication date: 1956-01-17
Anticipated expiration: 1973-01-17

Description

Jan. 17, 1956 c. D. REED ETAL SLOTTING MACHINE FOR MINERODS 4 Sheets-Sheet 1 Filed Oct. 25 1951 Jan. W, 1956 c. n. REED ETAL 2,730,73U

SLOTTING MACHINE FOR MINE RODS Filed Oct. 25, 1951 4 Sheets-Sheet 2 Jan. W, 1956 c. D. REED ETAL Y X SLOTTING MACHINE FOR MINE RODS Filed OCT. 25, 1951 4 Sheets-Sheet 3 wW/m f r I Jan. 17, 1956 c. D. REED EI'AL Wwfi SLOTTING MACHINE FOR MINE RODS Filed Oct. 25, 1951 4 Sheets-Sheet 4 United States Patent 2,730,730 SLOTTING MACHINE FOR MINE RUDE Claude D. Reed, Harry C. Felty, and Jay W. Hackett,

Lebanon, and Carl C. Hottenstein, Richland, Pa., as-

signors to Bethlehem Steel Company, a corporation of Pennsylvania Application October 25, 1951, Serial No. 253,098 20 Claims. (Cl. 10-11) This invention relates to a method and apparatus for slotting mine roof rods and more especially to mechanism for this purpose applied to a thread rolling machine similar to the one shown in U. S. Patent No. 1,783,796, issued to J. A. Kinney, December 2, 1930.

Prior to adopting the present method of hot slotting,

we tried burning and sawing the slots in the end of the rods. These methods were slow and expensive. We also applied this method to an upsetter machine.

In the machine illustrated the slotting attachment is applied to the forward end of the reciprocating cross-head, although any upsetter or forging machine of similar type with a reciprocating cross-head could be adapted for use for this purpose.

One of the objects of the invention relates to the mechanism for controlling the intermittent feeding of the rod blanks to the machine.

Another object of the invention is the idea of providing a wedge to form a slot in the blank in combination with a pair of positively driven rolls during the reciprocating movement of the cross-head.

These mine roof rods are formed with a slot at one end and the opposite end is threaded, and are used in mines to assist in supporting the mine roof similar to the manner disclosed and described in the application of E. E. Roecker, Serial No. 220,797, filed April 13, 1951, for Mine Roof Bolting.

Another object of our invention relates to the manner of closing the slot in the end of the rod after the slotting operation and for preventing the slotted ends of the rods from welding together.

Another advantage of our invention relates to forming the front end of the slotting tool notched. Forming the front end of the slotting tool in this manner, it is found, prevents flashes forming on the two sides of the slot, and in addition the slot is slightly spread apart at its outer end which facilitates the entry of the wedge which is adapted to be inserted therein.

With these and other objects in view which will become apparent in the following description and disclosure, this invention comprises the novel construction and combination hereinafter described and more particularly pointed out and defined in the appended claims.

Having thus given a general description of the objects of our invention we will now in order to make the same more clear, refer to the annexed four sheets of drawings forming a part of this specification and in which like characters of reference denote like parts.

Figure 1 is a side elevation of the machine embodying our invention.

Fig. 2 is an transverse section taken on the line 22 of Fig. 1.

Fig. 3 is a detail view illustrating the manner of heating the end of the blank for a mine roof rod.

Fig. 4 is a top plan view of the machine showing the slotting device attached to the reciprocating cross-head inthe back position in full lines and in the forward position in dotted lines.

Fig. 5 is a detail view illustrating the manner of feeding and centering the rods and for ejecting the rods after the slotting operation.

Fig. 6 is atop plan view of the slotting tool.

Fig. 7 is an inner side elevation of the slotting tool as shown in Fig. 6.

ice

Fig. 8 is a top plan view of the slotting device drawn on a larger scale with the cross-head in the forward position at the end of the slotting operation.

Fig. 9 is a side elevation of the slotting device in the position shown in Fig. 8.

Fig. 10 is a detail of the profile of one of the guide rolls.

Fig. 11 is a vertical transverse section taken on the line 11-11 of Fig. 8.

Fig. 12 is a vertical transverse section taken on the line 1212 of Fig. 9.

Fig. 13 is a vertical longitudinal section taken on the line 13-13 of Fig. 11, and

Fig. 14 is a side elevation of the end portions of one of the mine roof rods drawn on a larger scale.

Referring now to the various characters of reference on the several views of the drawings, the numeral 1 indicates the bed plate of the machine having front and rear portions 2 and 3 respectively. The front portion 2 has an upwardly extending back portion 4 and a front upwardly extending portion 5 between which is located a slide-way 6 for the reciprocating cross-head 7.

The cross-head 7, which reciprocates in the slide-way 6 has a vertical extension 8 formed integral therewith having horizontal adjustable bottom liners 9, and between the back face of the cross-head and the upwardly extending inner face of the back portion 4 with liners 10.

A cap plate or hinder 11 of inverted channel shape having downwardly extending flanges 12 and 13 is mounted and adjustably secured to the top of the back portion 4 by means of bolts 14 at the top and on one side by set bolts 15 which extend through flange 12. The opposite flange 13 engaging the extension 8 is formed on the cross-head 7. By adjusting the bolts 14 and 15 any loose play between the cross-head 7 and the liners 9 and 10 may be taken up or adjusted as will be readily understood.

Mounted on the rear portion 3 of the bed plate is a main drive shaft 16 having at each end thereof a fly wheel 17, the hubs 18 of which are keyed to the drive shaft.

Mounted centrally on the main drive shaft 16 is keyed a pair of pinions 19 and 20 which engage a pair of spaced crank gear wheels 21 and 22 respectively which are keyed to the inner ends of shafts 23 and 24 and connected together by means of a crank pin 25 for attaching one end of the connecting rod 26, the opposite end of the connecting rod being pivoted as at 27 to the end of the reciprocating cross-head 7.

The slotting machine for the mine rods is attached to the forward end of the cross-head 7, comprising a crosshead stock 28 secured to the cross-head to which is welded a spacer block 29 and a guide block 30.

A drive shaft 31 has one end portion. journaled in the cross-head stock 28 and the opposite end portion journaled in a bracket support 32 which is secured to the cross-head stock .28. Mounted on the drive shaft 31 at an intermediate point is a gear 33 which meshes with and is actuated by means of a rack bar 34 which is supported by means of an angle 35 attached to the top of the front upwardly extending portion 5 of the bed plate 1. Mounted on the drive shaft 31 between the bracket support 32 and the gear 33 is a drive gear 36 for actuating

gears

37 and 38 on the

guide roll shafts

39 and 40 for positively rotating the

guide rolls

41 and 42 for advancing or retracting the mine rod blanks 43 to or from the slotting tool 44 mounted adjacent to the rear of the

guide rolls

41 and 42 and attached to the cross-head stock 28. Attached to the guide block 30 is a guide plate 45 for an adjusting bar 46 having an inclined face 47 for engaging the inclined inner end 48 of the slotting tool 44 for longitudinally adjusting the same. The adjusting bar 46 is vertically adjusted by means of a set bolt 49 which is threaded into a clamp 50 mounted on top of the cross-head stock 28.

arsograo The slotting tool 44 is wedge shaped having an inner longitudinal flange 51 which extends into a groove 52 1n the cross-head stock 28 which is somewhat longer than the flange 51 to allow for adjustment. The slotting tool 44 is further provided with a slot 53 for a "bolt 54 which is threaded into the cross-head stock '28 for securing the slotting tool imposition. The front end of the slotting tool is notched as at 55 having inclined endedg'es. Forming the front end of the slotting tool in this manner, it is found, prevents flashes forming on the two sides of the slot 56 and in addition the slot is slightly spread apart at its outer end as at 57 which facilitates the entry of the roof wedge.

It will be noted that the gear 33 which is actuated by the rack bar 34 is slightly smaller than the gears '36, 37 and 38 for driving the guide rolls 4 1 and 42. In our original experiments with this unit we had actuated the guide rolls directly with the rack which gave a slower motion than the stroke of the cross-head and also the passes of the rolls were made concentric. In this manner some difficulty was encountered "with a slight upsetting of 'the rod in the slotting operation in that on the return stroke of the cross-head the slot 53 would more or less weld together. -In modifying the gearing by increasing the mur'nb'er of teeth and size of the

gears

36, 37 and 38 to increase the outer peripheral speed of the guide rolls we found that 'this condition was practically-eliminated.

Another feature found to workout satisfactorily was to turn the groove on the guide rolls slightly eccentric to allow a wider opening to compensate for the slightly upsetting action caused by the slotting operation.

l O shows the profile of one of the guide =ro1'ls for a29/3 2" rod, and for clearness this figure is drawn four times the actual size, but the dimensions stated are correct.

As indicated more clearly in Figs. 9, 1 2 and 13, top and bottom guides "58 and 59 are attached to the crosshead "stock .28 by means of bolts 60 for guiding the split ends 61 of the rod.

As indicated in Fig. 9 a small jet of air is directed on the nose of-the slotting .tool 44 by a pipe 62, thus adapted to cool the tool and remove any scale deposited thereon,

and a substantial quantity of water is directed on the top and bottom of the slotting tool by

pipes

63 and 64 thereby forming scale on :the split surface of the bar to prevent welding of the split end of the bar together when the cleft in the blank is closed.

Referring now to the manner of feeding the blanks to the machine, and more particularly to Figs. :1, .2, 3, 4 and 5-,:the cold mine rod blanks 43-first have-one end inserted into the heating chamber 65 of a furnace -66 having a hearth 67 as indicated in Fig. -3 and the ends are heated to aforg ing temperature. Extending outwardly from the forward end of the bed plate 1 is an I-beam 68 upon which is mounted bearings 69 for supporting a shaft 70 and a ;pair of spaced side plates 71 having downwardly inclined top edges 72, each provided with a centering notch 73. An escapement arm 74 has one end pivoted as at 75 to each side plate 71 and the pposite end of each of said .escapernent arms 74 is provided with a finger 76 and a recess 77 having a contact face 78. The two escapelnent arms 74 are connected together by means of a shaft '79 to the central portion of which is attached one end of an adjustable link 80, the other end of which .is pivoted as at 81 to one end of a lever 82 which is supported centrally on the shaft 70 and its other end is pivoted as at 83 to the top end of a piston rod 84 of an air cylinder 85 which is pivoted at its lower end, as at $610 a bracket 87 attached to the I-beam 68.

A locking arm "88 is pivoted centrally as at 89 to each of the 'spa'ced side plates 71 each provided with a hook shaped upper end 190 and a lower end .pivotally attached as at "91 'to the piston rod 92 of an air cylinder 93w hich is attached to the side pla'te'71 as at 94.

' After "heating the ends of the -rod blanks a plurality of the blanks are rolled in succession out ofth'e furnace 66 onto an inclined chute 95 "down which they roll until they engage stops 96 which are attached to the upper end of the side plates 71 as indicated in Figs. 2 and 5. Several blanks may be retained by the stops 96 and the mechanism shown in these two .figures is actually atmagazine feed with an escape motion to pick the lower blank of a number that have been placed near the top oflthe inclined edge 72 of the side; plates 71.

As indicated in Figs. 2 and 5, a blank 43 ha'sbeented to the centering notches 73 and :the locking arms 88 actuated by the cylinders 93 for thehook ends to close the mouth of the notches in the position .it assumes for the slotting operation. The cross-head 7 then moves forward and the 'end of the blank is slotted at the end of the forward stroke of the cross-head as illustrated in Figs. 8, 9 and 13, and to prevent the blank from moving away from the cross-head during the slotting operation a back stop 97 is provided to engage the outer end of the blank. After the cross-head of the machine has moved back far enough for the guide rolls "41 and 42 to release the slotted end of the blank .the locking arms 88 are then actuated by the air cylinders 93 and the hook ends 90 moved back far enough to release the slotted end of the blank, as indicated in dotted lines in Fig. 5.

The escapement arms 74 are then raised 'by means of the air cylinder 85 into the dotted line position :as shown in Fig. 5. in this position the finger 76 will engage the lower blank which is in contact with the stops "9'6 and raise it above the stops and allow it to roll into the recess 77 and engage the contact face 78, and at the same time the blank in the centering notches 73 will be raised and roll down the inclined edges 72 of the side plates 71 and deposited in the cradle 98. When the escapernent arm 741's returned to the full line position the blank engaging the contact face 78 in the recess '77 will be released and will roll down into the centering notches 73. The above described operation will then be repeated. The cross head 7 can reciprocate continuously. There is no clutch or stop mechanism so that the motions of the magazine take place during part of the back stroke and part of the forward stroke of the cross-head. Air to "the cylinders 85 and 93 is controlled by separate valves 99 and 1'00 respectively which are mounted on the downwardly extending flange 13 of the cap plate 1'1. These valves are opened and closed by dogs 1 01 and "102 mounted on the reciprocating cross-head.

As indicated in the'drawings only two sets of clamping clFlilSillG used, but more clamping arms may be used in the same manner depending on the length of the rod blanks.

Although we have shown and described our improvemerits in considerable detail, we do not wish to be limited to the-exact and specific details shown and described, but may use "such substitutions, modifications or equivalents thereof, as are-embraced within the scope of our inven- -.tion,:oras pointed out-in theclaims 'Weclairn '1. A machine icr'sl'otting the end portion of "a blank, a cross-head, means for reciprocating 'the cross-head, a slotting device mounted on the reciprocating cross-head, comprising a slotting wedge, a pair of rolls carried on the cross-head in advance of the wedge for guiding tlre'blank to the wedge, and means actuated 'by the movement of the cross-head for positively rotating the pair of rolls in alternately rcversing directions.

2. A machine for slotting the end portion of a rod hlank, a cross hea'd, means for reciprocating thecrosshead, a slottingdeviee mountedonthe reciprocating crosshead, comprising a slotting wedge, and 'a pair .Of .rolls carried on the cross-head in advance of't'he wedge, means 'actuated by the movement o'fthe cross-head in one direc 'tion for rotating the rolls and thereby guiding the blank to the wedge .to slot the end ,portion of the blank on \the forward stroke of the cross-head, said means being'also i actuated to reverse the rotation of the rolls .andthereby to close the slot when the blank is withdrawn from the rolls on the backward stroke of the cross-head.

3. A machine for slotting rod blanks, means for heating one end portion of the blanks to a forging temperature, a reciprocating cross-head, means for feeding and ejecting a rod blank to and from the machine during each reciprocation of the cross-head, means for transferring the rod blanks from the heating means to the feeding means, a slotting device mounted on the reciprocating cross-head, comprising a slotting wedge, and a pair of rolls carried on the cross-head in advance of the wedge, and means actuated by movement of the cross-head to drive said rolls first in one direction for guiding the rod blanks to the wedge to slot the heated end portion of a blank on the forward stroke of the cross-head and then to drive the rolls in the opposite direction to close the slot when the blank is withdrawn from the rolls on the backward stroke of the cross-head.

4. A machine for slotting rod blanks, a reciprocating cross-head, means for feeding and ejecting a rod blank to and from the machine in succession during each reciprocation of the cross-head, a slotting device mounted on the reciprocating cross-head, comprising a slotting wedge having its pointed end notched with inclined end edges to prevent flashes forming on the sides of the slot during the slotting operation, means for centering and holding the rod blank during the slotting operation, a pair of positively driven rolls having grooved passes formed slightly eccentric for guiding the rod blanks to the wedge to slot the end portion of a rod blank and to allow for a slight expansion of the slotted end of the blank on the forward stroke of the cross-head and to close the slot when the rod blank is withdrawn from the rolls on the backward stroke of the cross-head.

5. In a machine for slotting mine rod blanks, means for heating one end of. each mine rod blank, a crosshead, means for reciprocating the cross-head, a slotting device mounted on the cross-head, comprising a wedge for slotting the heated ends of the mine rod blanks, a pair of rolls mounted on the cross-head in advance of the Wedge for guiding the mine rod blanks to the wedge for slotting the heated ends of the mine rod blanks, and means actuated by movement of the cross-head for driving the rolls at a greater peripheral speed than that of the cross-head and thereby obviating welding of the rod ends.

6. A machine for slotting mine rod blanks, a crosshead, means for continuously reciprocating the crosshead, a slotting device mounted on the cross-head, comprising a wedge for slotting the ends of the mine rod blanks, a pair of positively driven rolls having a pass for guiding the mine rod blanks to the wedge for slotting the ends of the mine rod blanks, a furnace for heating one end of each mine rod blank, a chute for receiving the blanks from the furnace, side plates having inclined upper edges for receiving the blanks from the chute, centering notches formed in the top edge of the plates for holding the mine rod blanks in alignment with the pass of the rolls, and a backstop adapted to engage the front end of the mine rod blank to prevent the said blank from moving away from the cross-head during the slotting operation.

7. A machine for slotting mine rod blanks, comprising a bed plate having a slideway formed therein, a crosshead mounted in the slideway, means for continuously reciprocating the cross-head, a slotting device mounted on the cross-head having a wedge for slotting the ends of the mine rod blanks, means for positively driving a pair of rolls mounted on the cross-head having a pass for guiding the mine rod blanks to the wedge for slotting the ends of the mine rod blanks on the forward stroke of the cross-head, means for reversing the rotation of the pair of positively driven rolls for closing the slot on the backward stroke of the cross-head, means operated by the reciprocation of the cross-head for successively feeding and clamping the mine rod blanks for the slotting opera tion, and a backstop adapted to engage the front end of the mine rod blank to prevent the said blank from moving away from the cross-head during the slotting operation.

8. A machine for slotting mine rod blanks, comprising a bed plate having a slideway formed therein, a crosshead mounted in the slideway, means for continuously reciprocating the cross-head, a slotting device mounted on the cross-head having a wedge with. its pointed end notched for slotting the ends of the mine rod blanks, rolls carried on the cross-head in advance of the wedge and having a pass for guiding the mine rod blanks to the wedge for slotting one end of the mine rod blanks, means actuated on the forward stroke of the cross-head for driving the rolls and reversing the direction of drive on the return stroke, means for directing a jet of air on the notched end of the wedge, and means for directing a substantial quantity of water on the top and bottom of the wedge during the slotting operation thereby forming scale on the split surface of the bar to prevent welding of the split end of the bar together when the slot is closed by the operation of the rolls during the retraction of the cross-head.

9. A machine for slotting mine rod blanks, comprising a bed plate having a slideway formed therein, a crosshead mounted in the slideway, means :for continuously reciprocating the cross-head, a slotting device mounted on the cross-head having a wedge for slotting the ends of the .mine rod blanks, a pair of positively driven rolls having ,a pass for guiding the mine rod blanks to the wedge for slotting the ends of the mine rod blanks, a furnace for heating one end of each mine rod blank, a chute for receiving the blanks from the furnace, side plates having downwardly inclined upper edges for receiving the blanks from the chute, a stop secured to each side plate for retaining one or more blanks as they roll from the chute, notches formed in the top edges of the plates for centering and holding the mine rod blanks in alignment with the pass of the rolls, means for raising the blanks above the stops and for feeding them in succession into the centering notches, a locking arm for retaining the blanks in the centering notches during the slotting operation, means for releasing the locking arm from the blank after the slotting operation and means for ejecting the blanks from the machine.

It). A machine for slotting mine rod blanks, comprising a bed plate having a slideway formed therein, a crosshead mounted in the slideway, means for continuously reciprocating the cross-head, a slotting device mounted on the cross-head having a wedge for slotting the ends of the mine rod blanks, rolls carried on the cross-head in advance of the wedge and having a pass for guiding the mine rod blanks to the wedge, means actuated by the cross-head for driving the rolls while the Wedge is slotting the ends of the mine rod blanks on the forward stroke of the cross-head and reversing the direction in which the rolls are driven during the backward stroke of the cross-head to place the slotted portions of each blank together, means for heating one end of each mine rod blank, means for transferring the heated blank to the slotting device, and means actuated by the reciprocation of the cross-head on the backward stroke for ejecting the mine rod blanks from the machine in succession.

ll. A machine for slotting mine rod blanks, comprising a bed plate having a slideway formed. therein, a crosshead mounted in the slideway, means for continuously reciprocating the cross-head, a slotting device mounted on the cross-head having a wedge for slotting the ends of the mine rod blanks, a pair of positively driven rolls having a pass for guiding the mine rod blanks to the wedge for slotting the blanks, a furnace for heating one end of each blank, a chute for receiving the blanks from the furnace, side plates having downwardly inclined upper edges, a stop attached to each side plate for retaining one or more blanks as they roll from the chute, a notch 7 formedlin the top :edge of each side plate for centering and holding the rod blanks in alignment with the pass of the trolls, alocking for holding the blank in the centering notches during the slotting operation and for releasing the blanks'after the slotting operation, an escapernent arm having one end pivoted to each of the side plates and the other end adapted for vertical swinging movement, a finger and a recess having a contact face formed on the swinging end of each of the escapement adapted when the swinging ends of the escapement arms are moved upwardly to raise the blank above the eentering notches and eject .it from the machine and tor the fingers to engage ,a blank and lift it over the stops and deposit it in the recesses against the contact faces to straighten the posit-ion of the rod, and adapted when the swinging ends of the escapement arms are lowered to allow the blank to roll into the centering notches.

:12. -A machine for slotting mine rod blanks, comprising a-bed plate having a slideway formed therein, a crosshead mounted in the slideway, means for continuously reciprocating thecross-head, aslotting device mounted on the cross-head having va wedge for slotting the ends of the mine rod blanks, a pair of positively driven rolls carried on the cross-head in advance of the Wedge and having a passfergguiding the mine trod blanks to the wedge, means actuated by the cross-head for driving the rolls while the wedge is slotting the blanks, an inclined chute having pivoted thereon an escapement arm adapted to feed and eject the mine rod blanks from the machine in succession, a docking arm coa'cting with the escapemcnt arm for holding the mine rod blank during the slotting operation, and :means actuated in response to the movement of the cross-head for operating said escapement and locking arms.

13. A machine for slotting rod blanks, comprising a bedplate having a slideway formed therein, a cross head mounted in the slideway, means for reciprocating the cross-head, aslottin'g device mounted on the cross-head having a wedge for slotting the end of the rod blank, a driver'shaft, a gear mounted on the drive shaft at an intermediate point, a stationary rack bar meshing with the gear for rotating the drive shaft during the reciprocation of the cross-head, a gear mounted on the end of the drive shaft, a pair of shafts geared together at one end and .drivenby the gear on the end of the driveishafteach having a roll :mounted on the other end having a pass for ,guiding the rod blank to the wedge for slotting the rod blank, and means for feeding and ejecting the rod blanks from the machine in succession during the reciprocation of the cross-head.

- -l4. (A machine for slotting rod blanks, comprising a reciprocating cross-head, means for continuously reciprocating the cross-head, .a slotting device mounted for reciprocation with the cross-head having a wedge for slotting the ends of the .rod blanks, a drive shaft, a mounted .on the drive shaft at an intermediate point, a stationary rack bar meshing with the gear for rotating the drive shaft during the reciprocation of the cross-head, a ,gear mounted on the end of the drive shaft, a pair of shafts geared together at one end and driven by the gear .on the end of the drive shaft, each shaft of said pair of shafts having a roll :mounted on the other end having a pass for guiding the rod blank to the wedge for slotting the rod blank and for retracting the rod blank from the wedge and closing the slot, and means actuated during the reciprocation of the cross-head for feeding antlejech ,ing .the rod blanks from the machine in succession.

15. A machine .for slotting rod blanks, comprising a reciprocating cross-head, means 'for continuously reciprocating the cross-head, a slotting device mounted for reciprocation with the cross-head having a wedge with its pointed end notched for slotting .one end of the rod blank, apair of positively driven rolls having .a pass for guiding the rodblanks to the wedgecfor slotting the :rod blank and for retracting the rodblank from the wedge and closing the slot with the .onter end of the slot slightly spread apart, a furnace for heating one end of the .rod blanks, a chute for receiving the blanks as they are rolled from the furnace, side plates having downwardly inclined upper edges, a -stop attached to each side plate near the upper end for retaining one or more blanks as they roll from the :chute, a notch formed in the top edge of each side plate for centering and holding the rod blanks in alignment with the pass of the rolls, a locking arm, a fluid pressure cylinder connected to the locking arm and adapted to be actuated during the reciprocation of the cross-head for holding the blank in the centering notches during the slotting operation and for releasing the blanks after the slotting operation, an 'escapement arm having one end pivoted to each of the side plates and the other end adapted for vertical swinging movement, a finger and a recess having a contact face formed on the swinging :end of each of the escapement arms adapted when the :swinging end is moved upwardly to raise the blank above the centering note]: to eject it from the machine and .for'the finger to engagethe blank and lift it over the stops and deposit it in the recesses against the contact faces to straighten the position of the rod blank and adapted when the swinging end of the escapement arm is lowered to allow the blanks to roll into the centering notches, and a fluid pressure cylinder having a link connection with the :escapement arm and actuated during the reciprocation of cross-I'head.

16. A machine for slotting mine rod blanks comprising a bed plate, having a slideway formed therein, a crosshead mounted in the slideway, means for continuously reciprocating the cross-head, aslotting device mounted on the cross-head having a wedge for slotting the ends of the mine rod blanks, means for adjusting the wedge, rolls carried onwthe cross-head in advance of the wedge and havinga pass'for guiding the mine rod blanks to the wedge, means iactuated byithe cross-head for driving the rolls forward while the wedge is advancing and slotting the blanks and reversing the roll drive when the wedge is being retracted, the outer peripheral speed of the rolls being greater than that 'of the stroke of the cross-head, an inclined chute having pivoted thereon an escapement arm and fluid pressure means operatively linked to the escapement arm and operated by the cross-head to feed and eject the mine rod blanks from the machine during each reciprocation of cross-head.

'17. A machine for slotting rod blanks comprising a reciprocating cross-head, means for continuously reciproeating the cross-head, a slotting device mounted for reciprocation with the cross-head having a wedge for slotting one end of the rod blank, 21 pair of positively driven rolls having apass for guiding the rod blank to the wedge for slotting the'rod blank on the forward stroke of cross-head and 'for'retracting the rod blank from the wedge and closing the slot on the backward stroke of cross-head, a furnace for heating one end of the rod blanks, a chute for receiving the blanks as they are rolled from the furnace, side plates having'downwardly inclined upper edges, a stop attached to each side plate near the upper end for retaining one or more blanks as they roll from the chute, a notch formedin the top edge of each side plate for centering and holding the rod blanks in alignment with the pass of the feed rolls, locking .arms for holding a blank in the centering notches during the slotting operation and for releasing the blank after the slotting operation, an escapement arm having one end pivoted to each of the side plates and the other end adapted for vertical swinging movement, a finger and a recess having a contact face formed on the swinging end of each of the escapement arms adaptedwhen the swinging end of the arm is moved upwardly to raise the blank above the centering notches to eject the said blank from the machine and for the finger teen-gage a rodblank :and lift'it over the stops and deposit it :in the recesses against :the contact rfaces to straighten theposition of the rod blank, and adapted when-said swing ing ends of the escapement arms are lowered for the blank to roll into the centering notches, separate air cylinders for actuating the locking arms and the escapement arms controlled by separate valves which are opened and closed by dogs mounted on the cross-head and actuated during its reciprocation.

18. A machine for slotting mine rod blanks, comprising a bed plate having a slideway formed therein, a cross-head mounted in the slideway, means for continuously reciproeating the cross-head, a furnace for heating one end of the mine rod blanks, means for feeding a mine rod blank from the furnace to the machine during each reciprocation of the cross-head, a slotting device mounted on the crosshead having a wedge for slotting the heated ends of the mine rod blanks, a pair of rolls carried on the cross-head in advance of the wedge and having a pass for guiding the mine rod blanks to the Wedge, means operated by the cross-head for driving the rolls in one direction during the forward stroke of the cross-head to slot the end of the mine rod blank and to drive the rolls in the reverse direction to close the slot during the backward stroke of the crosshead, and means operated by the cross-head for ejecting a slotted blank from the machine during each backward stroke of the cross-head.

19. In a machine for slotting rod blanks, a slotting device, a blank holder, reciprocating means for causing relative motion between said slotting device and said blank holder, grooved guide rolls for the blank carried on the reciprocating means adjacent the forward edge of said slotting device, and means actuated by the reciprocating means for positively driving said guide rolls in alternately reversing directions.

20. In a machine for slotting rod blanks, a slotting device, a blank holder, reciprocating means for causing relative motion between said slotting device and said blank holder, grooved guide rolls for the blank carried on the reciprocating means adjacent the forward edge of said slotting device, and means actuated by the reciprocating means for positively driving said guide rolls in alternately reversing directions at a greater peripheral speed than the speed of reciprocation of said slotting device and blank holder.

References Cited in the file of this patent UNITED STATES PATENTS 372,497 Smith Nov. 1, 1887 376,914 Russell Jan. 24, 1888 389,239 Myers Sept. 11, 1888 1,783,796 Kinney Dec. 2, 1930 2,207,872 Ostberg July 16, 1940 2,223,342 Fehse Dec. 3, 1940 2,338,652 Lefere Jan. 4, 1944 2,402,794 Whitman June 25, 1946 2,405,141 I-Iibbard Aug. 6, 1946 2,691,785 White Oct. 19, 1954