US1299987A - Method and machine for making treads. - Google Patents

Description

C. MESSICK.

METHOD AND MACHINE FOR MAKING TREADS.

APPLICATION FILED APR.6.19H.

. Patented Apr. 8, 1919.

' 3 SHEETS-SHEET I.

avwcnfoz q vi tmwoca C. MESSICK.

METHOD AND MACHINE FOR MAKING TREADS.

APPLICATION FILED APR. 6.19M.

Patented Apr. 8, 1919.

3 SHEETSSHEET 2- Ill/II y ww Z W 6 1 C w" :4. n 3.721..

C. MESSICK.

METHOD AND MACHINE FOR MAKING TREADS.

APPHCATION FILED APR.6.19H.

1,299,987., Patented Apr. 8,1919.

3 SHEETS-SHEET 3.

'I IIIIIIIIIIIIIIIIIIIIIIIIIllIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 930i twcosco: (June :1 1'0;

I meager.

rm sra rss PATENT orrrca.

CHARLES MESSICK, 0F HACKENSACK, NEW JERSEY, AS SIGNOR, BY DIRECT AND MESNE ASSIGNMENTS, TO ELECTRICAL CONVEYING MACHINERY COMPANY, A CORPORA- 'I'ION OF NEW YORK.

\ METHOD AND MACHINE FOR MAKING TEE-ADS.

(to give mechanical strength and to afford attachment to the stair or other installa tion), and the surfacing being usually of carborundum or other granular abrasive material embedded in a binder of lead or other soft metal.

The manufacture of such treads, particularly in a wholesale, commercial manner, has hitherto been unsatisfactory, though different schemes-have been attempted, without as yet marked success. Among other objections, it has been found that when it is sought to combine the carborundum with molten lead,-the former will rise to the surface without being properly fixed throughout the binder; again, difliculty has been found in properly securing the carborundum-lead surfacing to the base-plate, for example because the mechanical means (such as undercut grooves and the like) which have been previously attempted, present a slippery metal surface to the foot of the pedestrian, thus impairing the efliciency of the anti-slip feature.

In carrying out my present invention, I

, first provide a two-part mold, within which I'place a suitable base-plate (preferably of tinned sheet steel or the like) and then fill the mold with carborundum' or other suitable abrasive material, and secure the parts of the mold together temporarily, as by spring-clips, to constitute a casting-unit;

then such units are passed, successively 'through a tankcontaining molten lead (or other suitable binder), whereby the carbo-' rundum and lead are simultaneously and permanently bound together and bound to the tinned base-plate. Each casting-umt in turn serves to propel the units in front of it, and is itself propelled by the succeeding units of the series.

Specification of Letters Patent.

Application filed April 6, 1911. Serial lQ'o. 619,258.

Patented Apr. 8, 1919.

. More specifically, in carrying outv this process, I employ a preferred form of apparatus that comprises four main features, to wit: (1) means for receiving each castingunit and removing the temporary clamps, while holding the parts of the unit together and delivering the same, to the feedingmechanism; (2) means for feeding forward each casting unit in turn, and thereby feeding the units in front of it through the molten lead; (3) the casting-means, containing the molten binder (lead) and 1) means forcooling and delivering the molds and their contents.

The inventipn consists of the new method of manufacturing anti-slip treads or similar articles; and also of the new apparatus for carrying out the process, and particularly of the molten-lead tank provided with a continuous passageway for the molds, with out permitting loss of the molten material. The invention further comprises the new forms of the features above indicated, as well as the various combinations thereof. The invention further comprises the various details of construction and arrangement as hereinafter set forth and claimed.

My invention will be best understood in connection with the following description of a preferred embodiment of the apparatus for carrying it out. as illustrated in the annexed drawings. But the invention is not limited to the precise construction and arrangement of parts, or to the specific details of operation therein set forth; and especially my new process may be carried out by other and different mechanical means than those shown.

In the annexed drawings,

Figure 1 is a side view of the complete machine;

Fig. 2 is a longitudinal section through the machine, the central portion being broken away;

-Fig. 3 is a top view of the same, the central portion being broken away as in Fig. 2;

Fig. 4 is a transverse section through theline 4-4 of Fig. 3, viewed from the right; Fig. 5 is a similar view through the line 55 of Fig. 3;

Fig. 6 is a transverse section. on a larger scale, through the line 6-6 of Fig. 1, viewed from the-right;

Figs. 7-11 illustrate, on a larger scale, the

mold, the casting-unit, and the finished tread, wherein Fig. 7 is a plan of the casting-unit, with its cover partly broken away to show the contents;

Fig. 8 is a side view of the same; M

Fig. 9 is a transverse section through the mold and the base-plate therein;

Fig. 10 is a perspective of a completed anti-slip tread; and

Fig. 11 is a section of a modified form of tread, with an extra thick nosing. Referring first to Figs. 79, the reference-numeral 21 indicates a mold, shown as a long, narrow, shallow pan, open at both ends, and having a longitudinallycorrugated floor. Upon the floor is laid a tinned iron base-plate 23, which eventually is to become a portion of the tread, as will be more fully described. The mold is closed by the cover or cope-plate 22, which is bent down at one end as shown at the right of Fig. 8, to close one end of pockets formed on the face of the base-plate by the corrugations of the. mold 21. The mold and the cope, containing the base-plate, are clamped together by the temporary clamps 24. Carborundum or other granular abrasive is poured into the open mouth ofthe pockets, and after they are completely filled a little shellac may be applied to the mouths to prevent the carborundum from jarring out .in handling. Although the cope is apparently fitted closely upon the mold, nevertheless, there is suflicient space at the hairline junction to permit the molten lead to enter, reach the carborundum, and fill all the voids within the mold.

A mold thus filled and clamped constitutes a casting-unit. Preferably a number of these units will be prepared before hand, in readiness for the casting operations. In casting, one of these units is introduced, by hand, into the front of the appaously,the casting-units being thus .fed

continuously through the molten lead and through the cooling-zone, until they and their finished castings are successively discharged at the rear of the machine, where the castings can be removed from tneir respective molds.

The apparatus as a whole is seenin-Fig.

1. At the center is the casting-mechanism which comprises an open-ended trough 10, having a longitudinally inclined floor, and being supported upon legs 14-15 and steadied by braces 16. At the right is shown the extension-plate or slide-bar 18, steadied by braces 17, which carries the stripping and the feeding mechanisms; and at the left are the cooling-means 67. The casting-units, as 25, are introduced at the upper end (at the right of Fig. 1), and discharged at the left. Fig. 2 shows also one of the intermediate casting-units 26, and still another unit 27 about to emerge from the coolingregionat the end of the machine.

The receiving and stripping mechanism comprises the stationary wedge-shaped stripper 28, projecting from a block 29 that is secured upon the outer end of the T- a shaped slide 18, and a similarly-shaped upper stripping-plate 30, yieldingly secured above the lower stripper, as by means of the depending rods and'springs 3132.' The upper face of the stationary stripper 28 is centrally and longitudinally channeled out to receive the casting-unit, this guide-channel being preferably made somewhat flaring at its entrance (as indicated by dotted lines at the right of Fig. As each unit- (25) is introduced, the sloping noses of the strippers 28 and 30 strip oif the springsurf-ace to receive the casting-units and also to receive the horizontal member of the/ upper gripping-jaw 34, which latter is an inverted T in cross-section, having a longitudinal and centrally-located upwardly-extended flange. Horizontal guide-pins 5253 extend from each side of the upper jaw 34, and lie in vertical slots in the marginal flanges of jaw 3'3,whe reby the two jaws.

are locked together longitudinally but can have relative movement in vertical direction. In the depending arms of the lower jaw is mounted the transverse shaft 47; the

floating counter-shaft 48 is located in a LOO slot in the top of the upper jaw; and two l floating pivots 45 and 46 (lying in the prolongation of the same line) are connected to the shafts 47 and 48 respectively by the pairs of parallel links shown in Fig. 5. This construction, as seen in Fig. 1, con stitutes a toggle so arranged that when the pivots 45 and 46 are forced forward (to the left in Fig.1), the two jaws 33 and 34 are forced together; whereas movement of the pivots in the opposite direction tends to separate the two jaws.v A set-screw 49, turning through the counter-shaft 48 and provided with a jam -nut, abuts against the upper jaw 34 and provides vertical adjustment' of the parts. Two. rearwardly extending springs 50 and 51 are secured to the depending arms of the lower jaw 33, and are connected to the lever 54 that is pivoted near the rear end of the slide-bar 18. By moving the lever 54 from the. depending position indicated in Fig. 2 into the position indicated in Fig. 1, the grippingjaws are drawn rearward bodily. A setscrew having a handwheel 55, turns in a lug 56 (Fig. 4) dependin from the block 29, and is alined with an a utment 57 (Fig. 3) carried by the lower jaw- 33, for adjustably limiting the rearward travel of the gripping-jaws.

Rising from the block 29 are two arms 38 and 39, in which turns the transverse shaft 36, driven by power, as through the belt-wheel 37 (Fig.3). On this shaft are mounted the eccentrics 41 and 42 carrying the pitmen 43 and 44, which latter are shown as having lost-motion engagement withthe floating-pivots 45 and 46. Preferably, the parts are so adjusted that when the lever 54 is in the depending position indicated in Fig. 2,'the rotation of the power-shaft 36 causes the pitmen to reciprocate idly upon the floating-pivots; but when the lever 54 is raised into the position shown in Fig. 1, this brings the pivots 45 and 46 within reach of the. two abutments of the pitmen. This furnishes an intermittent feed: During the for ward travel of the pitmen the gripping-j aws are first brought together (to seize the interposed casting-unit) and then moved forward bodily; and during the rearward movement-of the pitmen, the gripping-jaws are first forced apart (releasing the castingunit) and then drawn rearwardly.

To prevent any rearward travel of the casting-unit, a sort of sliding pawl is provided, comprising the eccentric quadrant 35 journaled loosely upon the power-shaft 36 and carrying a pivoted dog 40, the upper stripper-plate 30 being cut-away to permit the nose of the dog and the quadrant to enter the channel. As shown in Fig. 2, the maximum eccentricity of the quadrant 35 is in the horizontal direction and its minimum eccentricity inthe-vertical direction. When the first casting-unit 25 is inserted, its forward end abuts against the dog 40 and forces the latter forward, lifting the quadrant, until the farther travel of the unit releases the dog, whereupon the quadrant 35 drops back and grips the casting-unit 25, holding it against any tendency to rearward movement.

The casting-mechanism comprises the openended main trough 10, having the longitudinally-inclined floor 11 and the side-walls 12 and .13, within which is the floating or lead-pot 58, whose bottom is parallel to floor 11 and has an opening (near the forward and lower end thereof, see Figs. 1, 2, and 6) that affords an outlet into the mam trough. Preferably the rear end-walls of the floating-trough have hooks or shoulders -62 (Fig. 2), engaged by the transverse-bar L the tension of the spring-devices at 64 and 65 clamping the casting-unit. Preferably, when the device is not in operation a blank or dummy of iron, of the same dimensions as a casting-unit, is interposed between the floor of the main trough 10 and the bottom of the float-trough 58. Beneath the troughs 10 and 58 is a plurality of gas burners from the pipe 59.

Beneath the continuation of the floor 11 of the main trough 10, is a water-compartment 60; and at the rear of the floatingtrough 58 is carried another water-compare ment 67. 66 is a filling of asbestos, interposed between the melting-trough 58 and the water-compartment 67. Cold water is introduced into compartment 60, through pipe 68; thence it passes, through pipe 69, into the compartment 67, whence it escapes through pipe 70. 61 is a table or continuation of the floor of the trough, upon which the cooled casting-units are discharged. The cooling-compartment 67, in addition to cooling the casting-units, cools the adjacent portions of the side-walls of the troughs; and thus any molten lead that may tend to leak out in the clearance between the troughs 10 and 58, is frozen and forms a lead-packing to prevent the leaking out of the lead.

At the outset, one of the dummy-plates having been placed beneath the floating lead-pot 58 (or left there from a previous operation), suflicient lead or other binder having been supplied in the floating-trough 58, the burners 59 having been lighted, and

the troughs and contents having been heated up more than sufliciently to melt the latter,- the operator starts the revolution of the shaft 36, and then inserts a casting-unit 25 into the channel between the strippers and 7 starts it forward; the spring-clamps are removedby the wedges, and the clamp-action of springs 3132 is substituted, while the unit is being pushed forward and the quadrant-pawl 35 is caused to engage upon the top of the unit; then the operator inserts a second casting-unit, which is acted upon as before, and meantime the first unit (having entered the space between the thenseparated gripping-jaws 3334) is gripped by the jaws and carried forward, the quadrant 35 preventing any tendency to rearward movement; and so on continuously, the first casting-unit shoving the dummy out of its way and entering the casting-channel, where it is subjected to the casting operation, and thence being forced by the succeed ing units into the cooling-zone between water-compartments 60 and-67, where it is properly cooled and the casting solidified;

and finally the unit is discharged along'the extension-table 61, where the same operator, or an assistant, will remove thecope from the mold and take out the casting and put it to one side.

I have thus described my invention with great particularity of detail, but only for the sake of clearness, and as applied to manufacturing anti-slip treads, since the invention could be applied to the manufacture of other articles, and parts may be omitted and other parts substituted, and modifications may be made in the construction and arrangement of the parts, without departing from the spirit of my invention. For instance, some other stripping-mechanism might be made use of, or the stripping-device might be omitted altogether and the cope held upon the mold by hand until inserted into the machine. Again, some other form of feeding-device might be substituted in place of the gripping-jaws 8334; and, indeed, the mold and cope with their contents might be held together by hand, and I inserted directly into the casting-channel. So, also, it is obvious that various other forms of cooling-devicescould be employed;

or, if desired, the mold and its contents,

while still hot, could be discharged from the casting-mechanism, and allowed to cool in the open air. But the best results are obtained by the combination of the inter-related mechanisms which cooperate in simultaneously or successively stripping, holding, guiding, 'feeding, casting, and cooling the casting-units, to provide the continuous manufacture of the completed product.

'I-Iaving thus described my invention, '1 claim: I

1. In-a tread-manufacturing apparatus, the combination of springwith wedge-shaped noses for ing-units or two-part molds therefrom temporary clips, feeding-mechanism for receiving said units from said aws and propelling the same in a continuous series, and a casting-chamber and a coolingchamber forming a continuous passageway in front of said feeding-mechanism.

2. In a tread-manufacturing apparatus,

recelving castand removing the combination of an open-ended trough having an inclined bottom, a second trough located therein and having an opening that cl'amped jaws ing-chamber, means for clamping said troughs upon said spacing-means, said spacing-means serving to close the outlet of said chamber, and means for heating said trough.

Ina tread-manufacturing apparatus, the combination of an open-ended trough, a second trough located therein and having an opening that communicates with the outer trough, means such as a: blank dummy or a casting-unit for spacing the inner trough above the floor of the outer trough to constitute a casting-chamber and to close the outlet therefrom, and means for clamping said troughs upon said spacingmeans.

4L. In a tread-manufacturing apparatus, the combination of an open-ended trough, a second trough located therein and having an opening that communicates with the firstnamed trough, and means such as a blank dummly or a casting-unit for spacing the inner trough above the floor of the outer trough to constitute a casting-chamber and to close the outlet therefrom.

5. In a tread-manufacturing apparatus, the combination of a casting-trough for molten lead o the like and a cooling-region in front thereof, with a continuous passage-way through the two, and means for automatically feeding a series of molds or castingunits continuously through said passageway.

6. The combination With a tread-manufacturing apparatus which comprises a castingchamber with a continuous passage therethrough, of a casting-unit adapted to pass through said passage and to close the outlet therefrom, consistin of a two-part mold having detachable c ips securing together the parts of said mold.

7 In a machine for making treads, a casting-machine comprising a: lead-pot having a troughlike bottom adapted to act as a slide through which a mold may be slid, and a movable cover for the slide, cooling-devices at the lower end of the slide, and a propelling-mechanism to propel a mold and contents through the slide.

8. In a machine for making treads, a casting-machine comprising a lead-pot having a troughlike bottom adapted to act as a sllde through which a mold may be slid, one memmer of the slide being movable to adapt it to compensate for unevenness of the mold and for expansion or contraction, and cooling-devices at the lower end of the slide.

7 9. In a casting-machine to cast articles of soft metal, a machine comprising a leadpot, a mechanism to propel a mold bodily through same, and molds capable of being propelled bodily through the lead-pot, whereby a series of heated-mold-castings may be made in the molds during their passage through the lead-pot.

10. In a casting-apparatus, the combination of a lead-pot having a passageway therethrough, a mold adapted to travel bodily through said passageway, and means for propelling said mold bodily through said passageway.

11. In. a casting-apparatus, the combination of a-casting-trough, for molten lead, a movable member mounted yieldingly therein to exert pressure downward, and a cooling-device adjacent one end of the latter to freeze the lead. located in the adjacent portion of the space between the side-walls of said trough and said movable member.

- 12. The herein-described process of making treads, which consists in providing the face of a foundation plate with fusible material, holding a mass of abrasive particles in definite form against the face ofsaid plate, and uniting said particles into a homogeneous mass and simultaneously connecting said mass to said plate by filling the interstices with the molten metal.

13. The process of binding granular particles in place upon the surface ofa metal plate, which consists of introducing a soft metal into the interstices between the granu- I lar particles themselves and between the same and said plate.

14. The process for making treads and the like, which consists of enveloping the several elements in a mold, then passing the filled mold through a lead-pot to introduce the lead into the mold, and then subsequently withdrawing and cooling the mold and contents.

15. The process for casting lead in treadplates, which consists in enveloping the tread-plate in a mold, then passing same through a lead-pot to cast, and subsequently coolin same.

16. he process of heated-mold-casting, which consists in propelling a series of molds bodily into and through and out of a leadot. p 17. The process of manufacturing antislip treads, which consists in temporarily positioning carborundum or other abrasive material in proper relation to a foundationplate within a suitable two-part mold to constitute a casting-unit, then sub ecting said units to heat and pressure while simultaneously introducing molten lead or other binder into the interior thereof, whereby the carborundum is bound together and simultaneously bound to the foundation-plate.

18. The process of manufacturing antislip treads, which consists in temporar ly positioning carborundum or'other abraslve material in proper relation to a foundationplate within a suitable mold to constitute a casting-unit, then propelling said unlt through a heated casting-chamber containing molten lead or other binder, whereby the mold and its contents are heated and the molten binder introduced into the abrasive and the abrasive bound together and simultaneously bound to the foundation-plate.

and of attaching the soft metal to the base plate.

20. In a tread manufacturing apparatus, the combination of an open ended trough, a second trough located therein, and means such as a blank dummy or a casting unit for spacing the inner trough above the floor of the outer trough to constitute a casting chamber and to close the outlet therefrom.

21. In a tread manufacturing apparatus, the combination of a casting trough for molten lead or'the like and a cooling region in front thereof with a continuous passageway through the two, and means for feeding molds or casting units through said passageway.

2-2. The combination with a tread manufacturing apparatus which comprisesacasting chamber having a continuous passageway therethrough, of a casting unit or the like adapted'to pass through said passage and to close the outlet therefrom.

23. In a machine for making treads, a casting machine comprising a lead pot having a trough-like ortion adapted to act-as a slide through which a mold may be slid, a movable cover for the slide and cooling devices at the lower end of the slide.

24. In a, machine for making. treads, a castin machine comprising a lead pot having a trough-like member. adapted to act as a slide through which a mold maybe slid Slug a .cooling device at the lower end of the 25. The process of manufacturing antislip treads which consists in temporarily positioning carborundum or other abrasive material in proper relation to a foundation. plate within a suitable mold to constitute a casting unit, then subjecting the unit to heat and pressure while simultaneously introducing molten lead or other binder into the interior of the mold in the interstices of the abrasive material whereby the carborundum is bound together and simultaneously bound to the foundation plate.

26. The process of making treads composed of a base of strong material surmount ed by a wearing surface of soft material having grit embedded therein, which consists of introducin soft material in the in-, terstices of the gr1t and attaching the soft material to the strong material.

27. The process of making treads composed of a base of strong material coated with a surface of soft material and having material and embedding granular material therein.

28. In a casting machine, the combination of a guide device provided with an entrance and an exit, a plurality of mold-sections in matin relation arranged to pass through the guide device and to hold a lengthy body of molten metal to be solidified into a casting, means for 'progressively moving the mold-sections and the contents thereof through the guide device, andcooling means adjacent the path of travel of the moldsections for solidifying the contents of the mold-sections progressively in relation to the length thereof before emerging from the exit of the guide device.

29. In a casting machine,"the combination of a guide device having a movable springmaintained guide member and provided with an entrance and an exit, a plurality of mold-sections held in mating relation b the spring-maintained guide member an arranged to pass through the guide device and to hold a lengthy body of molten metal to be solidified into a casting, means for progressively moving the, mold-sections and contents thereof through the guide device, and cooling means adjacent the path of travel of the mold-sections for solidifying the contents of the mold-sections progressively in relation .to the length thereof before emerging from the exit of the guide device.

CHARLES mission.

Images