US1501918A - Sharpener for drill steels - Google Patents

Sharpener for drill steels Download PDF

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US1501918A
US1501918A US680688A US68068823A US1501918A US 1501918 A US1501918 A US 1501918A US 680688 A US680688 A US 680688A US 68068823 A US68068823 A US 68068823A US 1501918 A US1501918 A US 1501918A
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cylinder
valve
raising
motive fluid
clamping
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US680688A
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Arthur E Peters
Mortimer S Parkhill
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Ingersoll Rand Co
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Ingersoll Rand Co
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21JFORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J7/00Hammers; Forging machines with hammers or die jaws acting by impact
    • B21J7/20Drives for hammers; Transmission means therefor
    • B21J7/46Control devices specially adapted to forging hammers, not restricted to one of the preceding subgroups
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21KMAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
    • B21K5/00Making tools or tool parts, e.g. pliers
    • B21K5/02Making tools or tool parts, e.g. pliers drilling-tools or other for making or working on holes
    • B21K5/06Dressing, e.g. sharpening rock drills

Definitions

  • This invention relates to drill sharpening and forging machines, but more particularly to the pneumatically operated machines for sharpening drill steels.
  • the type of drill sharpening device to which this invention is more particularly applicable is that in which there is provided a clamping head operated by a large piston on its downward stroke and a small piston for raising or separating the clamping elements.
  • the raising cylinder in which the smaller piston reciprocates is operated with motive fluid only at such times when it is desired to raise the clamping member, at other times the fluid is exhausted slowly through a suitable valve to form a cushion.
  • the object of the cushion is to prevent the clamping jaws from striking together under the full force of motive fluid and in this manner to eliminate the tremendous shocks which might weaken the machine.
  • the object of this invention is to enable the cushion to be formed in the smaller cylinder and to be controlled by the main valve, which controls-the other operating parts of the machine.
  • the bleed or release of motive fluid from the raising cylinder is permitted throughthe controlling valve proper, thereby eliminating unnecessary apparatus and providing a simple construction.
  • Another object of the invention is to provide a free exhaust for the motive fluid from the various operative portions of the machine.
  • Figure 1 is a side elevation of a pneumatic drill sharpening machine, partly in section disclosing the interiorof the controlling valve and the driving portions of the Figure 2 is a vertical section of thefoontrolling valve in the valve chest showing the valve in its first operating position.
  • Figure 4 is a vertical section of-' the valve and valve chest showing thethird operating position
  • 7 T Figure 5 is a section taken through the valve and valve chest showing the exhaust passages and connections valve. 7
  • the machine is provided with a base A upon which is mounted a main cylinder B to accommodate a large piston C which terminates at its lower end in a smaller piston D, the base A being bored accurately tore'ceive thesmaller 'pis ton, and being closed by base plug A.
  • the upper portion of the cylinder B forms an anvil block E upon which the drill steels, are forged and clamped as isusual in machines of this type.
  • a clamping head I is adapted to be raised and lowered upon reciprocation of the piston C and is attached to that piston by means of the cross head rods G extending through the anvil block E and bolted to'the piston C by means of the nuts H.
  • the apparatus is such that-when motive fluid, such as for instance compressed air, is admitted above the large piston C, the cross head 'F is lowered with great force to act as a hammer. against the drill steel placed on the anvil block E, and if desired the. pressure. may bemaintained'in the cylinder- B which is hereinafter termed the clamping cylinder, in order to grip the steel as in a vise.
  • the raising of the cross head F is accomplished by exhausting the air from the clampingcylinder B and admitting compressed air to the raising cylinder-J below the. smaller piston D.
  • Dollying operations are per-formed upon a drill steel clamped between the cross formoving; the v head F and 'the anvil block E means of dolly apparatus of any suitable typehaving a dolly cylinder as indicated at K. Suitable air connections are. provided. to
  • valve chest It.
  • the ports and passages in the valve chest, which are controlled by the valve L, are shown in Figures 2, 8, a and 5.
  • the motive fluid is supplied to the valve chest through a port S from a suitable source.
  • the raising cylinder is supplied with air through a pipe connection T, which i associated in the valve chest with a port U similar to the pipe connection V, which conducts air to the dolly cylinder K from Motive fluid isadmitted to the clamping cylinder 3 through a port X in thevalve chest, which I connects with the cylinder B through a passageway Y in the wall of'the cylinder.
  • the exhaust from the various cylinders is conducted through individual paths, that of the clamping cylinder passes through a port Z to atmosphere, while the exhaust from the dolly cylinder is led out through the structure of the dolly cylinder itself as is usual in devices of this character.
  • the exhaust from the cylinder is restricted and escapes through small perforations a, Z), and in the lower enlarged portion of the valve L.
  • the arrangement of the ports U S, X, IV and Z is such that the valve has three consecutive operating positions.
  • the port I] communicate with the supply port S through the bore of the chest so that motive fluid flows directly into the raising cylinder J.
  • the clamping cylinder B is in direct communication with a chamber (Z which leads to atmosphere both around the inner shell 6 of the valve chest through a passageway f, or through the hollow bore of the valve.
  • the passageway f is provided to give suliicient freedom of exhaust to the large quantity of air to'be exhausted'from the clamping cylinder.
  • the port X is blanked by the valve L. so that there is no sup-ply of air to the clamping cylinder and in addition, the port VV'associated with the dolly cylinder is closed.
  • the supply of motive fluid to the port W is cut off from the port-S by the larger diametered portion of the valve, and the port X is associated with the supply port S admitting air to the clamping cylinder B to depress the'piston C whereupon the cross head .F islowered toits clamplng or forging position. Simultaneously the exhaust port Z is closed, preventing the escape of motive fluid from the clamping cylinder and the dolly cylinder is cut off from the supply of motive fluid by the closure of the port W. In this position, the motive fluid in the raising.
  • valveL In its upward travel, the valveL uncovers the port W leading to the dolly cylinder and the pressure motive fluid is permitted to pass from the supply port S through the bore of the valve chest, through the port V1 to the dolly cylinder
  • the valve thus has three consecutive oper ating positions, the first shown in Figure 2, in which the raising cylinder is supplied with motive fluid to raise the cross head F, which permits the removal or insertion of the drill steel between the cross head F and the anvil block E.
  • the second position, shown in Figure 3 is for clamping or forging the drill steels between the anvil block E and the cross head F. In forging a drill steel the first two positions only may be used to shape the sides of the drill steel shank.
  • the third position shown in Figure l is useful to operate the dolly cylinder for sharpening or dollying the end of the drill previously clamped between the anvil blocl; E and the cross head F.
  • Suitable plugs indicated at g and 71- provide access to the interior of the valve chest R- and if desired, the chamber 7' which is closed by the plug it, may be used as reservoir for lubricant or a lubricating device, a for instance of the cartridge type.
  • the lower part of the valve chest through which the exhaust escapes to atmosphere may be provided with a plate bolted or otherwise suitably attached to cover the opening and may have a threaded aperture 0- therein by which a pipe coupling may be connected to lead oft the exhaust]
  • a clamping cylinder at raising cylinder and a dolly cylinder, a valve having three consecutive operating positions and adapted to connect a supply of motive fluid with said raising cylinder in the first'position and to exhaust the clamping cylinder to atmosphere; to as sociate said motive fluid supply with said clamping cylinder in the second position and. to bleed said raising cylinder; and in i Mill the third position to associate said clamping cylinder and said dolly cylinder with said motive fluid supply and to continue to bleed said raising cylinder.
  • a clamping cylinder, a raising cylinder and a dolly cylinder In a drill sharpening device, a clamping cylinder, a raising cylinder and a dolly cylinder, a valve having three consecutive operating positions and adapted to connect a supply of motive fluid with said raising cyl inder in the first position and to exhaust the clamping cylinder to atmosphere; to associate said motive fluid supply with said clamping cylinder in the second position and to bleed said raising cylinder; and in the third position to associate said clamping cylinder and said dolly cylinder with said motive fluid supply and to continue to bleed said raising cylinder, said valve being hollow to conduct the exhaust therethrough to atmosphere.
  • a valve having three consecutive operating positions and adapted to connect a supply of motive fluid with said raising cylinder in the first position; and to exhaust the clamping cylinder to atmosphere; to associate said motive fluid supply with said clamping cylinder in the second position, and to bleed said raising cylinder; and in the third position to associate said clamping cylinder and said dolly cylinder with said motive fluid supply and to continue to bleed said raising cylinder; said valve being hollow to conduct the exhaust fluid therethrough to atmosphere, and provided with an aperture therethrough communicating with the raising cylinder and the interior of the valve.
  • a valve having three consecutive operating positions and adapted to connecta supply of motive fluidwith said raising cylinder in the first position and to exhaust the clamping cylinder to atmosphere; to associate said motive fluid supply with said clamping cylinder in the second position, and to bleed said raising cylinder; and in the third position to associate said clamping cylinder and said dolly cylinder with said motive fluid supply to continue to bleed said raising cylinder, said valve being hollow to conduct the exhaust fluid therethrough to atmosphere, and provided with a plurality of apertures through the valve to maintain a fixed degree of bleeding of the raising cylinder to atmosphere in the second and third positions of the valve.
  • a clamp ing cylinder, a raising cylinder and a dolly cylinder having three consecutive operating positions and adapted to connect a supply of motive fluid to said raising cylinder in the first position and to exhaust said clamping cylinder to atmosphere; to associate said motive fluid supply with said clamping cylinder in second position and to bleed said raising cylinder; and in the third position to associate said clamping cylinder and said dolly cylinder with said motive fluid cylinder but continue to bleed said raising cylinder, said valve being provided with means to maintain a fixed degree of bleeding of the raising cylinder to atmosphere in the second and third positions of the valve.

Description

July 22, 1924. 1,501,918
A E. PETERS ET AL SHARPENER FOR DRILL STEELS Filed Dec. 14. 1923 2 Sheets-Sheet 1 THEIR ATTOR Y Jul v 1924. 1,501,918
- A. E. PETERS ET AL SHARPENER FR DR ILL STEELS Filed Dec. 14. 1923 f 2 Sheets-Sheet 2 machine.
Patented July 22, 1924.
NlTE
- oEFIc v ARTHUR E. rn'rnns AND MORTIMER s. ranxnrnn. or nrrrmngon, oononnno',
srolvons 'ro INe RsoLL-nann COMFANYJQOF PORATION on NEW JERSEY.
JERSEY 0 w NEW q ea faq ia snanrnnnn non DRILL. s'rEELs' Application filed December 14, 1923. Serial No. 68Q,688,
To all whom it may concern:
Be it known that we, ARTHUR E. Farms and MORTIMER S. PARKHILL, citizens of the United States, and residents of Littleton, county of Arapahoe, and State of Colorado, have invented a certain Sharpener for Drill Steels, of which the following is a specification, accompanied by drawings.
This invention relates to drill sharpening and forging machines, but more particularly to the pneumatically operated machines for sharpening drill steels.
The type of drill sharpening device to which this invention is more particularly applicable, is that in which there is provided a clamping head operated by a large piston on its downward stroke and a small piston for raising or separating the clamping elements. The raising cylinder in which the smaller piston reciprocates, is operated with motive fluid only at such times when it is desired to raise the clamping member, at other times the fluid is exhausted slowly through a suitable valve to form a cushion.
The object of the cushion is to prevent the clamping jaws from striking together under the full force of motive fluid and in this manner to eliminate the tremendous shocks which might weaken the machine.
The object of this invention is to enable the cushion to be formed in the smaller cylinder and to be controlled by the main valve, which controls-the other operating parts of the machine. In the particular embodiment hereinafter described, the bleed or release of motive fluid from the raising cylinder is permitted throughthe controlling valve proper, thereby eliminating unnecessary apparatus and providing a simple construction.
Another object of the invention is to provide a free exhaust for the motive fluid from the various operative portions of the machine.
@ther objects of the invention will become apparent from thefollowing description taken in. conjunction with the drawings, in which there is illustrated a practical embodiment, and in which 'Figure 1 is a side elevation of a pneumatic drill sharpening machine, partly in section disclosing the interiorof the controlling valve and the driving portions of the Figure 2 is a vertical section of thefoontrolling valve in the valve chest showing the valve in its first operating position.
Figure 4 is a vertical section of-' the valve and valve chest showing thethird operating position, and 7 T Figure 5 is a section taken through the valve and valve chest showing the exhaust passages and connections valve. 7
Referring to the drawings, and more partic'ularly to' Figure 1, the machine is provided with a base A upon which is mounted a main cylinder B to accommodate a large piston C which terminates at its lower end in a smaller piston D, the base A being bored accurately tore'ceive thesmaller 'pis ton, and being closed by base plug A. .The upper portion of the cylinder B forms an anvil block E upon which the drill steels, are forged and clamped as isusual in machines of this type. A clamping head I is adapted to be raised and lowered upon reciprocation of the piston C and is attached to that piston by means of the cross head rods G extending through the anvil block E and bolted to'the piston C by means of the nuts H. The arrangement of the. apparatus is such that-when motive fluid, such as for instance compressed air, is admitted above the large piston C, the cross head 'F is lowered with great force to act as a hammer. against the drill steel placed on the anvil block E, and if desired the. pressure. may bemaintained'in the cylinder- B which is hereinafter termed the clamping cylinder, in order to grip the steel as in a vise. The raising of the cross head F is accomplished by exhausting the air from the clampingcylinder B and admitting compressed air to the raising cylinder-J below the. smaller piston D. Dollying operations are per-formed upon a drill steel clamped between the cross formoving; the v head F and 'the anvil block E means of dolly apparatus of any suitable typehaving a dolly cylinder as indicated at K. Suitable air connections are. provided. to
the raising cylinder J, the clamping cylinder B and the dolly cylinder K, the distribution of air for actuating the variou devices beL-.-
by a lever, Q mounted on the-,exteirior-of the,
a port W in the valve chest.
valve chest It. The ports and passages in the valve chest, which are controlled by the valve L, are shown in Figures 2, 8, a and 5. The motive fluid is supplied to the valve chest through a port S from a suitable source. The raising cylinder is supplied with air through a pipe connection T, which i associated in the valve chest with a port U similar to the pipe connection V, which conducts air to the dolly cylinder K from Motive fluid isadmitted to the clamping cylinder 3 through a port X in thevalve chest, which I connects with the cylinder B through a passageway Y in the wall of'the cylinder. The exhaust from the various cylinders is conducted through individual paths, that of the clamping cylinder passes through a port Z to atmosphere, while the exhaust from the dolly cylinder is led out through the structure of the dolly cylinder itself as is usual in devices of this character. In order to form a cushion within the raising cylinder J below the smaller piston D, the exhaust from the cylinder is restricted and escapes through small perforations a, Z), and in the lower enlarged portion of the valve L.
The arrangement of the ports U S, X, IV and Z is such that the valve has three consecutive operating positions. In its first position, as shown in Figure 2, and in which the valve L is moved to its lower operating position, the port I] communicate with the supply port S through the bore of the chest so that motive fluid flows directly into the raising cylinder J. At this position of the valve L, the clamping cylinder B is in direct communication with a chamber (Z which leads to atmosphere both around the inner shell 6 of the valve chest through a passageway f, or through the hollow bore of the valve. The passageway f is provided to give suliicient freedom of exhaust to the large quantity of air to'be exhausted'from the clamping cylinder. Also in this first position,'the port X is blanked by the valve L. so that there is no sup-ply of air to the clamping cylinder and in addition, the port VV'associated with the dolly cylinder is closed.
' Upon raising the valve L to its second operating position 'as shown in Figure 3,
the supply of motive fluid to the port W is cut off from the port-S by the larger diametered portion of the valve, and the port X is associated with the supply port S admitting air to the clamping cylinder B to depress the'piston C whereupon the cross head .F islowered toits clamplng or forging position. Simultaneously the exhaust port Z is closed, preventing the escape of motive fluid from the clamping cylinder and the dolly cylinder is cut off from the supply of motive fluid by the closure of the port W. In this position, the motive fluid in the raising.
cylinder J is bled to atmosphere through the first perforation'a in the valve L. Under these conditions, the cross head F is lowered, forcing out the motive fluid from the raising cylinder J and the dolly cylinder is inactive there being no motive fluid being sup plied thereto.
In the third position of the valve, shown in. Figure 4 wherein. the valve L is raised to its uppermost extent, the motive liuid is still being exhausted from the raising cylinder through the perforations 0 and the valve is in such. position that the supply port S for the motive fluid is in communication with the port X to maintain the full pressure in the clamping cylinder B, the ex haust port Z of the clamping cylinder being still closed by the valve. In its upward travel, the valveL uncovers the port W leading to the dolly cylinder and the pressure motive fluid is permitted to pass from the supply port S through the bore of the valve chest, through the port V1 to the dolly cylinder The valve thus has three consecutive oper ating positions, the first shown in Figure 2, in which the raising cylinder is supplied with motive fluid to raise the cross head F, which permits the removal or insertion of the drill steel between the cross head F and the anvil block E. The second position, shown in Figure 3 is for clamping or forging the drill steels between the anvil block E and the cross head F. In forging a drill steel the first two positions only may be used to shape the sides of the drill steel shank. The third position shown in Figure l is useful to operate the dolly cylinder for sharpening or dollying the end of the drill previously clamped between the anvil blocl; E and the cross head F.
Suitable plugs indicated at g and 71- provide access to the interior of the valve chest R- and if desired, the chamber 7' which is closed by the plug it, may be used as reservoir for lubricant or a lubricating device, a for instance of the cartridge type. The lower part of the valve chest through which the exhaust escapes to atmosphere may be provided with a plate bolted or otherwise suitably attached to cover the opening and may have a threaded aperture 0- therein by which a pipe coupling may be connected to lead oft the exhaust] We claim: I
1. In a drill sharpening device, a clamping cylinder, at raising cylinder and a dolly cylinder, a valve having three consecutive operating positions and adapted to connect a supply of motive fluid with said raising cylinder in the first'position and to exhaust the clamping cylinder to atmosphere; to as sociate said motive fluid supply with said clamping cylinder in the second position and. to bleed said raising cylinder; and in i Mill the third position to associate said clamping cylinder and said dolly cylinder with said motive fluid supply and to continue to bleed said raising cylinder.
In a drill sharpening device, a clamping cylinder, a raising cylinder and a dolly cylinder, a valve having three consecutive operating positions and adapted to connect a supply of motive fluid with said raising cyl inder in the first position and to exhaust the clamping cylinder to atmosphere; to associate said motive fluid supply with said clamping cylinder in the second position and to bleed said raising cylinder; and in the third position to associate said clamping cylinder and said dolly cylinder with said motive fluid supply and to continue to bleed said raising cylinder, said valve being hollow to conduct the exhaust therethrough to atmosphere.
3. In a drill sharpening device, a clamping cylinder, a raising cylinder and a dolly cylinder, a valve having three consecutive operating positions and adapted to connect a supply of motive fluid with said raising cylinder in the first position; and to exhaust the clamping cylinder to atmosphere; to associate said motive fluid supply with said clamping cylinder in the second position, and to bleed said raising cylinder; and in the third position to associate said clamping cylinder and said dolly cylinder with said motive fluid supply and to continue to bleed said raising cylinder; said valve being hollow to conduct the exhaust fluid therethrough to atmosphere, and provided with an aperture therethrough communicating with the raising cylinder and the interior of the valve.
4. In a drill sharpening device, a clamping cylinder, a raising cylinder and a dolly cylinder, a valve having three consecutive operating positions and adapted to connecta supply of motive fluidwith said raising cylinder in the first position and to exhaust the clamping cylinder to atmosphere; to associate said motive fluid supply with said clamping cylinder in the second position, and to bleed said raising cylinder; and in the third position to associate said clamping cylinder and said dolly cylinder with said motive fluid supply to continue to bleed said raising cylinder, said valve being hollow to conduct the exhaust fluid therethrough to atmosphere, and provided with a plurality of apertures through the valve to maintain a fixed degree of bleeding of the raising cylinder to atmosphere in the second and third positions of the valve.
5. In a pneumatic drill sharpening device, a raising cylinder, a clamping cylinder and a dolly cylinder, a valve chest, a valve reciprocatory in said valvechest and having three operating positions in the first of V which motive fluid is supplied to said raising cylinder, and the clamping cylinder is exhausted to atmosphere; motive fluid being supplied to the clamping cylinder in the second position of the valve, and the raising cylinder being exhausted gradually to atmosphere, and in the third position the motive fluid being supplied to the clamping cylinder and the dolly cylinder while the supplied to the clamping cylinder in the sec- 0nd position of the valve, and the raising cylinder being exhausted gradually to atmosphere; and in the third position the motive fluid being supplied to the clamping cylinder and the dolly cylinder while the raising cylinder is gradually exhausted to atmosphere, said valve chest being provided with passages leading from both ends to atmosphere and said valve being hollow to conduct exhaust fluid therethrough and pro- I vided with a plurality of apertures extending to the interior of the valve for gradually exhausting the motive fluid from the raising cylinder in the second and third positions of the said valve.
7. In a drill sharpening device a clamp ing cylinder, a raising cylinder and a dolly cylinder, a valve having three consecutive operating positions and adapted to connect a supply of motive fluid to said raising cylinder in the first position and to exhaust said clamping cylinder to atmosphere; to associate said motive fluid supply with said clamping cylinder in second position and to bleed said raising cylinder; and in the third position to associate said clamping cylinder and said dolly cylinder with said motive fluid cylinder but continue to bleed said raising cylinder, said valve being provided with means to maintain a fixed degree of bleeding of the raising cylinder to atmosphere in the second and third positions of the valve. I
In testimony whereof we have signed this specification.
ARTHUR E. PETERS. MORTIMER S. PARKHILL.
US680688A 1923-12-14 1923-12-14 Sharpener for drill steels Expired - Lifetime US1501918A (en)

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