US2725854A

US2725854A - Combination air and water valve for rock drills

Info

Publication number: US2725854A
Application number: US349804A
Authority: US
Inventors: Earl B Lear
Original assignee: Chicago Pneumatic Tool Co LLC
Current assignee: Chicago Pneumatic Tool Co LLC
Priority date: 1953-04-20
Filing date: 1953-04-20
Publication date: 1955-12-06
Anticipated expiration: 1972-12-06

Description

E. B. LEAR Dec. 6, 1955 COMBINATION AIR AND WATER VALVE FOR ROCK DRILLS 4 Sheets-Sheet l Filed April 20, 1953 lNVENToR.

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ATroR/vfy Dec. 6, 1955 lCOMBINATION AIR AND WATER VALVE FOR ROCK DRILLS Filed April 20, 1953 HMH@ E. B. LEAR 4 Sheets-Sheet 2 INVENTOR. EARL LEAR BY @WMM/a. M

ATTORNEY Dec. 6, 1955 E. B. LEAR 2,725,854

COMBINATION AIR AND WATER VALVE FOR ROCK DRILLS Filed April 20, 1953 4 Sheets-Sheet 3 zfa 67 68 f6 101 81 az l I I w 61 41 INVENTOR.

f 141 EARL B. EAR

/ lz f2- BY 210 HZ 144 142 m A T TOR/v5 Y E. B. LEAR Dec. 6, 1955 COMBINATION AIR AND WATER VALVE FOR ROCK DRILLS 4 Sheets-Sheet 4 Filed April 20, 1953 www INVENTOR. EARL B EAR @WM/. M

ATTORNEY l 2,725,854 Patented De- 6 1955 CMBINATION AIR AND WATER VALVE FOR ROCK DRILLS Earl B. Lear, Utica,

Tool Company, New7 Jersey N. Y., assignor to Chicago Pneumatic New York, N. Y., a corporation of This invention relates to a combination air and water control valve for rock drills.

It is an object of the present invention to provide n a rock drill a single or common air and water control valve which will automatically effect, upon pulling the operating lever and before starting the drilling operation, the wetting with the water of the bottom of the hole being drilled ahead of the compressed air so as t prevent the dust from being blown out of the drilled hole and the lling of the surrounding air with rock dust.

It is another object of the invention tokprovide on the air valve element which controls the flow of air to the rock drill, grooves for receiving water from an inlet port and delivering it to an outlet port, wherein the water ports will be first opened as this air valve element is depressed to turn on the air, thus causing water to lirst ilow through a water tube into the drill steel and whereupon the further advance of the valve element causes the compressed air to llow through the automatic valve and operate the piston.

It is another object of the invention to provide in a valve body for a combination air and water control valve element a metered oil passage for delivering lubricating oil with the air to the enclosed operating parts of the rock drill.

Other objectsof the invention are to provide a single combination air and water control valve for rock drills, which is simple in construction, inexpensive to manufacture, has a minimum number of parts, compact and kept within minimum size, convenient and eicient in use.

For other objects and for a better understanding of the invention, reference may be had to the following detailed description taken in connection with the accompanying drawing, in which:

Figure 1 is a perspective view of a rock drillrembodying the combination air and water control valve of the present invention;

Fig. la is a side elevational view of a modified form of the invention with the handle lever extending along the inner or forward side of a hand grip portion;

Fig. 2 is an enlarged end vertical elevational view of the control lever and hand grip arrangementshown in Fig. l and as viewed generally on the line 2 2 thereof;

Fig. 3 is an enlarged side elevational view of the drill shown in Fig. 1 with portions Vof the air supply iitting and of the handle broken away to show the interior construction thereof; w

Fig. 4 is a fragmentary sectional view taken through the back head and generally upon line 4 4 of Fig. 1

Fig. 5 is an enlarged sectional view taken on line 5 5 of Fig. 3 and through the ratchet mechanism for turning the drill steel;

Fig. 6 is an enlarged sectional view of the back head taken generally on line 6 6 of Fig. 7;

Fig. 7 is an enlarged sectional view of the ldrill taken generally on line 7 7 of Fig. 6 and looking upon the front face of the back head;

Fig. 8 is a fragmentary sectional view taken on line 8 8 of Fig. 6 and through the Valve parts;

Fig. 9 is a longitudinal sectional view of the rock drill taken generally on line 9 9 of Fig. 3 and throughout the full extent of the rock drill;

Fig. 10 is a fragmentary sectional view of the backhead taken on line 10 10 of Fig. 8 and running along the water supply passage;

Fig. 11 is a fragmentary sectional View of the backhead view taken generally on line 11 11 of Fig. 8 and running along another portion of the water passage;

Fig. 12 is a fragmentary sectional view of the backhead taken on line 12-172 of Fig. 8 and running along an outlet Water passage that directs the water from the valve element to the water tube;

Fig. 13 is a fragmentary sectional view of the backhead taken on line 13 13 of Fig. 2 and running along the oil metering passage;

Fig. 14 vis a side elevational view of the valve bushing.

Referring nowto theV drawings, 20 represents a front head, Fig. 9 in which is disposed a chuck sleeve 21 and a chuck 22 axially aligned with one another. The chuck sleeve 21 has projections 23 that drivingly engage with slots 24 in enlarged end 25 of the chuck 22.

The chuck 22 receives a shank 26 of hexagonal section forming part of a drill rod 27 that has a bit head 28.

, The inward thrust of the drill rod 27 in the chuck 22 is limited by the engagement of with` the end of the chuck l22.

A tightly coiled drill rod retainer spring 30 is fixed on the end of the front Ahead 20 at 31 and so that the drill rod is held against outward displacement upon release from the chuck by the engagementV of its stop collar 29 with a reduced diameter end 32 of the spring 30.

A ratchet ring 33 having ratchet teeth 33', Figs. 5 and 9 surrounds piston 34 that is reciprocated within the front head 20 and in cylinder bushing 35 having an annular flange 36 against which cylinder part 37 abuts and is retained along with front valve seat 38, rear valve seat 38 and back head 39, against the front head 20 by long side rods 4i) and 41, Fig. 3, extending respectively through bosses 42 and 43 and made secure by the respective nuts 44 and 45. The headsV of the

respective bolts

40 and 41 are respectively seated in recesses 46 and 47 yand in the backhead 39.

The ratchet ring'33 (Fig.V 5) has three angularlyspaced radially-inwardly extending projections 48 that engage yrespectively with spiral grooves 50 of the piston 34 so that as the piston is thrust forwardly under pressurefthe ratchet ring 33'will be turned and locked with diametrically-disposed pawls 51 and 52 spring-pressed respectively by

spiral coil springs

53 and 54 engaging said pawls. The respective pawls are pivotable respectively in rounded slots 55 and 56 in the front head. The piston 34 is thus held against reverse rotational movement in the cylinder bushing 35.

The chuck sleeve 21 has radially inwardly-extending projections 57 (Fig. 9) thatextend into the straight grooves 50 of the piston 34 so that `the chuck sleeve 21 will beturned on each stroke of the piston 34 and in a like manner the chuck sleeve through the engagement of its projections 23 with .the slots 24 will causeY theV chuck 22 and the drill rod to be turned and so that the drill bit 28 will engage the work or drill hole at a different angle each time. A

y The piston .34 has an enlarged head 34 that is hollowed on its rear `face as indicatedat 58, Fig. 9 and. has ay central hole opening 59 extending throughout the length of the piston and through which there extends a waterl delivery tube 60 thate'xtendsffromV a hole 61 in its stop llange or collar 29 the backhead 39. The water tube 60"has a reduced por-v 3 tion 62 that extendsv through the hole 59. A packing washer 63 surrounds the tube 60 adjacent its connection with the hole 61 to prevent the leakage of water to the forward face of the backhead 39. A collar 64 (see Fig. 12) on the tube 60 abuts the packing washer 63.

The backhead 39 has a large air receiving chamber or hole 65, Fig. 8, that is internally threaded at 66 to receive a threaded bushing 67 having a hexagonal head 68 adapted to receive a wrench. Within the bushing 67 is a sleeve 69 having an enlarged end 70 engaging with the inner face of the bushing 67. The outer end of the sleeve 69 is threaded and projects outwardly beyond the head 68, Figs. l and 2, of the `bushing 67 and is threaded to receive an elbow fitting 71 to which a coupling connec-V tion 72 of an air hose 73 is made secure for supplying the air to the rock drill. Air under pressure is directed to the chamber 65 and against a common air and water valve element 74 having an air valve head 75 with a groove 76 therein in which is disposed a rubber sealing ring 77 adapted to prevent the ilow of air through a chamber 78 with which the air valve head 75 cooperates. This chamber or opening 78 is flared at 79 to provide a widened space communicating with the air chamber 65. A compression spring 80 extends intothe sleeve 69 to normally retain its flange 70 against the end face of the bushing 67 and to normally hold the air and water valve element 74 and its shank portion 81 against an arm 82 of a hand operating lever 83 (Fig. 2). The arm 82 of the hand operating lever 83 extends into a slot 84 in the backhead 39. The arm 82 cornes to rest against a threaded stop bolt 85 having a head 86 and threaded in opening 87, Fig. 8.

Within the air opening 78 is a bushing 88 (Fig. 6) through which the shank portion 81 of the valve element 74 slides The valve bushing 88 has two

external grooves

89 and 90 with

radial holes

92 and 93 respectively communicating with the interior of the bushing 88. The shank portion 81 of the valve element 74 has a reduced diameter portion 94, Fig. 6, providing an annular recess 95 of suflicient length to bridge the

radial holes

92 and 93 upon the valve element 74 being slid therebetween to thereby provide communication for the ow of water that is to be delivered to the bottom of the hole being drilled with the bit 28. As will be described later, the annular groove 89 and radial holes 92 are supplied with water at all times.

The shank portion 81 of the valve element 74 has two closely `spaced

grooves

96 and 97, Fig. 6, in which are respectively disposed rubber sealing rings 99 and 100. These rings when the valve element is in the closed position are disposed on opposite sides of the radial holes 92 so as to prevent theV leakage of water in opposite direc tions along the shank portion 81 of the valve element.

Spaced from the reduced diameter portion 94 of the shank portion 81 and from the groove 95 of the shank portion 81 is a groove 101, Fig. 6, having a sealing ring 102 to prevent the ilow of water from the groove 95 toward the end of the shank portion and out of the end of the bushing 88.

Adjacent the air sleeve 69 and at the top of the backhead is a water sleeve fitting 103, Figs. 1, 7, 8 and 10, that is threaded into a threaded hole 104 in the backhead 39. Connected to this tting 103 is a swivel fitting 105 of a water hose 106 Fig. 1, that has a male litting 107 to which a throttle valve 108 is connected and which has a turn knob 109 for controlling the ow of water to the rock drill. This valve 108 may be adjusted to throttle the iiow of the water in greater or lesser quantities as the demand requires.

Extending from the hole 104 as shown in Fig. 8, is a water passage 110 that communicates with a water passage 111 extending at an angle thereto that connects with the annular groove 89 of the bushing 88, Figs. 6, 8, I0 and l1. Accordingly, water is provided under pressure 4 at all times in the groove 89 and in the radial holes 92 of the bushing 88.

Upon the operating lever, 83 being depressed so that the end of the arm 82 presses against the end of shank portion 81 of valve element 74, the sealing ring 100 will move to the left of the radial holes 92, as viewed in Fig. 6, so that water under pressure is delivered to the large groove of the shank portion 81 and to the radial holes 93 and the groove 90 of the bushing 88. Water will thereafter ow from the groove 90 through a passage 112 (see Fig. 8) to the hole 61 and through the tube 60 fixed to the hole 61. Accordingly, upon a slight movement of the valve element 74 water will be sent through the delivery tube 60 and its reduced diameter portion 62 that extends through hole 59 in the piston 34 and through hole 27' in the drill rod 27 to the drill bit 28, and into the hole being drilled into the rock whereby to condition the hole and wet the same prior to the operation of the drill bit.

The hole 111, as shown in Fig. ll, is drilled from the side of the backhead so as to traverse the chamber 78 and is closed at its starting end by filling material 113 and the passage 112 in Fig. 12 is drilled from the side of the backhead in the same manner so as to traverse the chamber 78 and is closed at its starting end with lilling material 114.

When the valve element 74 is further depressed by the arm 82, the head 75 will extend into the dared end of the chamber 78 so as to admit air from the chamber 65 to the valve chamber 78. This air is then delivered through hole 116 to the front face of the backhead 39 (Fig. 9) and into a recess 117 therein. This recess 117 contains the rear valve seat 38 which has a rear circular recess 119 from which an annular series of holes 120 extend to deliver the air to the front of the rear valve seat 38 and to at lirst cause anged valve element 121 to move forwardly so that its ange 122 will engage with seat portion 123 on the front valve seat 38. The air will escape through the center of the Valve element 121 and into the cylinder 37 and against piston head 34 to move the piston 34 forwardly with a hammering action. The front valve seat 38 lies against a shoulder 124 on the rear end of the cylinder 37.

Upon the piston head 34 moving forwardly to uncover annular groove 125, the air in the cylinder will be exhausted through a passage 126 in a choker valve 127 havJ ing. an operating handle 128. This choker valve is retained in boss 129 on the exterior of the cylinder 37 which has an exhaust port 130.

With the air pressure being relieved on the rear of the piston, the compressed air at the front of the piston head 34' will be forced back through air passage 131 and against flange 122 of the valve element 121 so as to move the same rearwardly from the seat 38 and against seat portion 133 on the rear valve seat 38. Once this has been eiected, the air leaving the holes 120 of the rear valve seat 38' will move around the periphery of the ange 122 of the valve element 121 so as to maintain the valve element against the seat portion 133 of the rear valve seat 38 so that air under pressure may now flow into annular recess 134 of the front valve scat 38 and outwardly through radial pas sage 135 that communicates with the passage 131 to deliver air under pressure on the front side of the piston head 34' whereby the piston head will be moved rearwardly and returned for its next forward strokes.

As the forward edge of the piston head 34 uncovers the groove of the cylinder air will be exhausted through the choker valve 127 and exhaust port 130, and the valve element 121 will again move forwardly against seat portion 123 of the front valve seat 38.

Should it be desired to blow air to the drilled hole in the rock, the choker valve 127 is turned so that its passage 126 is aligned with a passage 136 in boss 129 and with the exhaust port 130. A radial passage in the front valve seat 38 communicates with the passage 134 at port 137 to drop the pressure and allow valve 121 to stay on its forward seat 123 whereby to divert the air through the valve 121 into the back end of the cylinder forcing the piston head 34' against the cylinder bushing 35. The air then traverses hole 59 of the piston and hole 27' in the drill steel 27 and will be exhausted through the end of the bit head 28 to remove the cuttings and dust from the drilled hole in the rock.

In the backhead 39 (Fig. 8) is an oil chamber 140 that extends vertically upwardly from the bottom of the backhead and is threaded as indicated at 141 at its open end to receive oil filler plug 142.

Extending laterally from the oil chamber 140 is an oil delivery hole 142, Figs. 4, 8, 13, that has a metering pin 143 therein to limit the flow of oil therethrough. This hole 142 communicates with a forwardly extending hole 144 that will finally deliver oil through the recess 117 of the backhead 39. This oil will commingle with the air being delivered to the rear valve seat member 38 and will pass to the cylinder to lubricate the inner wall thereof and to the bushing 35, and to such other parts Where lubrication is needed.

The metering pin 143 is removable through a threaded hole 145 in the side of the backhead 39 into which is in serted a plug 146. The plug 146 will maintain the metering pin against outward displacement and upon removal of the plug access can be had to the metering pin for the purpose of cleaning the same.

Integral with the backhead 39 and extending rearwardly therefrom are upper and lower handle supporting arms 154) and 151, Fig. 3. The lever 83 is pivoted on the supporting arm 151 at 152.

Extending vertically through the rear ends of the supporting

arms

150 and 151 is a through bolt 152 having a head 154 and a nut 155. On this bolt between the supporting

arms

150 and 151 is a hand grip sleeve 156 and lying below the arm 151 is a hand grip sleeve 157 and lying above the arm 150 is a hand grip sleeve 158. When nut 155 is tightened against spring washer 159, the bolt 153 will be drawn through the hand grip sleeves and they will be made rigidly connected to the supporting

arms

150 and 151. Each of the hand grip sleeves includes a metal bushing 166 and its outer portion is formed preferably of rubber in order that a good grip can be had upon the rock drill while the same is in operation. The control lever S3 is preferably formed of sheet metal and lits over the hand grip sleeve 157.

1n Fig. la, there is shown a modified form of a handle and control lever arrangement. The hand grip is disposed only between supporting

arms

150 and 151 as indicated at 162. This hand grip 162 is connected to the ends of supporting arms by a short bolt 163 and a nut 164 that is tightened against a spring washer 165.

Control lever arm 82 extends into slot 84, but its hand grip portion extends upwardly on the inner side of the hand grip 162 as indicated at 166 and upon squeezing the same the valve element 74 will be lifted. The return movement of both the control levers is effected by the Valve element spring 80 disposed within the air chamber 65 of the backhead 39.

It should now be apparent that there has been provided a rock drill having a single and common air and water control valve operated by the same control lever wherein the delivery or" water to the bottom of the rock drill hole is automatically effected upon the first pull of the same control lever so that its delivery is automatically insured prior to the delivery of air to the cylinder for working the rock drill and thereby to prevent the dust from being blown out of the drill hole and filling the surrounding air.

While various changes may be made in the detail construction, it shall be understood that such changes shall be within the spirit and scope of the present invention, as defined by the appended claims.

What is claimed is:

l. A backhead for a rock drill adapted to be attached to the front head and cylinder assembly thereof, having an elongated air chamber including an air supply inlet passage and an vair supply outlet passage, a valve bushing in said air chamber, passages for the delivery of water to and from said bushing, said bushing having two sets of radial openings longitudinally spaced from each other, one of said sets of radial openings being in connection with a passage arranged to deliver water to the bushing, the other of said sets of radial openings being in connection with a passage for conduction of water away from the bushing, a valve element having an air control head for controlling the flow of air through the air chamber and having a shank portion operable through said bushing, said shank portion having an annular groove adapted to bridge the radial holes of the bushing upon the valve element being longitudinally moved through the bushing and prior to the release of air to the air chamber.

2. A backhead for a rock drill adapted to be attached to the front head and cylinder assembly thereof, having an elongated air chamber including an air supply inlet passage and an air supply outlet passage, a valve bushing in said air chamber, passages for the delivery of water to and from said bushing, said bushing having two sets of radial openings longitudinally spaced from each other, one of said sets of radial openings being in connection with a passage arranged to deliver water to the bushing, the otherkoi:` said sets of radial openings being in connection with a passage for conduction of water away from the bushing, a valve element having an air control head for controlling the ow of air through the air chamber and having a shank portion operable through said bushing, said shank portion having an annular groove adapted to bridge the radial holes of the bushing upon the valve element being longitudinally moved through the bushing and prior to the release of air to the air chamber, and spaced rubber sealing rings on said shank portion on the opposite ends of the annular groove thereof and on the opposite sides of the radial inlet holes of the bushing to prevent leakage of inlet water along the shank portion when the valve element is in its closed position.

3. A` backhead for a rock drill adapted to be attached to the front head and cylinder assembly thereof, having an elongated air chamber including an air supply inlet passage and an air supply outlet passage, a valve bushing in said air chamber, passages for the delivery of water to and from'said bushing, said bushing having two sets of radial openings longitudinally spaced from each other, one of said sets of radial openings being in connection with a passage arranged to deliver water to the bushing, the other of said sets of radial openings being in connection with a passage for conduction of water away from the bushing, a valve element having an air control head for controlling the flow of air through the air chamber and having a shank portion operable through said bushing, said shank portion having an annular groove adapted to bridge the radial holes of the bushing upon the valve element being longitudinally moved through the bushing and prior to the release of air to the air chamber, spring biasing means cooperating with the air valve head to normally urge the same toward its closed position, and a control member engaging with the end of the shank and held in its outwardly extended position by the action of the spring upon the valve element.

4. A backhead for a rock drill adapted to be attached to the front head and cylinder assembly thereof, having an elongated air chamber including an air supply inletV passage and an air supply outlet passage, a valve bushing in said air chamber, passages for the delivery of water to and from said bushing, said bushing having two sets of radial openings longitudinally spaced from each other, one of said sets of radial openings being in connection with a passage arranged to deliver water to the bushing, the other of said sets of radial openings being n connection with a passage for conduction of water away from the bushing, a valve element having an air control head for controlling the ow of air through the air chamber and having a shank portion operable through said bushing, said shank portion having an annular groove adapted to bridge the radial holes of the bushing upon the valve element being longitudinally moved through the bushing and prior to the release of air to the air chamber, and handle supporting members extending outwardly from the back head, hand grip means connected between the handle supporting members, a control member pivotally connected to one of the supporting members and having a hand grip portion extending along the hand grip means so that the control member can be depressed while gripping the hand grip means to operate said valve element.

5. A backhead for a rock drill adapted to be attached to the front head and cylinder assembly thereof, having an elongated air chamber including an air supply inlet passage and an air supply outlet passage, a valve bushing in said air chamber, passages for the delivery of Water to and from said bushing, said bushing having two sets of radial openings longitudinally spaced from each other, one of said sets of radial openings being in connection with a passage arranged to deliver water to the bushing, the other of said sets of radial openings being in connection with a passage for conduction of water away from the bushing, a valve element having an air control head for controlling the flow of air through the air chamber and having a shank portion operable through said bushing, said shank portion having an annular groove adapted to bridge the radial holes of the bushing upon the valve clement being longitudinally moved through the bushing and prior to the release of air to the air chamber, spaced rubber sealing rings on said shank portion on the opposite ends of the annular groove thereof and on the opposite sides of the radial inlet holes of the bushing to prevent leaking of inlet water along the shank portion when the valve element is in its closed position, spring biasing means cooperating with the air valve head to normally urge the same toward its closed position, a control member engaging with the end of the shank and held in its outwardly extended position by the action of the spring upon the valve element, handle supporting members extending outwardly from the baclthead, and hand grip means connected between the handle supporting members, said control member pivotally connected to one of the supporting members and having a hand grip portion extending along the hand grip means so that the control member can be depressed while gripping the hand grip means to operate said valve elcmelli.

References Cited in the le of this patent UNITED STATES PATENTS 1,614,026 Gartin Jan. ll, 1927 1,889,441 Haas Nov. 29, 1932 2,320,905 Bateholts Tune l, 1943 FOREIGN PATENTS 401,892 Great Britain Nov. 23, 1933