US666757A - Motive-fluid-operated hammer. - Google Patents

Description

Patented 1an. -29,` 490|.

c. H. JOHNSON. MDTIVE FLUID O PERATED HAMMER.

(Application filled Mt. 2, 1900.)

(N0 Nudel.)

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CHARLES HARRIS JOHNSON, OF CHICAGO HEIGHTS, ILLINOIS, ASSIGNOR TO THE JOHNSON, PARFITT TOOL COMPANY, OF SPRINGFIELD, ILLINOIS.

lVlOTlVE-FLUID-OPERATED HAMMER.

SPECIFICATION-forming part of Letters Patent No. 666,757, dated January 29, 1901. Application filed March 2, 1900. Serial No. 7,081. (No model.)

To all wiz/m, it may concern: of the lever L or in other suitable manner,

Be it known that I, CHARLES HARRIS JOHN- and said motive-duid passage a of the han- SON, a citizen of the United States, residing dle connects with the motive-fluid passage b, at Chicago Heights, in the county of Cook, having the port b delivering into the cylin- 55 State of Illinois, have invented certain new der B.

and useful Improvements in Motive-Fluid- The handle A and throttle-valve T may be Operated Hammers; and Ihereby declare vthe of an approved construction, excepting that following to be a full, clear, and exact descripin order to secure the handle to the cylinder tion of the same, reference being had to the in a simple and effective manner I form the 6o a accompanying drawings, in Whichhandle with a flange l, which receives the Figure l is a longitudinal central section end of the cylinder B, and with an internal of a pneumatic hammer embodying my incollar 2, which takes over the end of the cylvention; and Fig. 2 is a sectional view of part inder B and is pinched between the end of of the cylinder and the piston or hammer, the cylinder and the flange of the cap D, 65 showingamodication in the arrangement of which closes the cylinder When said cap is the supplemental supply or admission port of in position. In order to lock the cap D and the piston. handle A to the cylinder B, I form a catch-l Like symbols refer to like parts wherever pocket 3 in the handle of the cylinder for the they occur. reception of a spring-pressed ratchet-dog 4, 7o

zo My invention relates generally to the con- Which engages a suitable notch in the head struction of what are termed valveless moof cap D, and said dog is confined in said tive-fluid-operated tools, and especially to pocket by an annular screw-plug 5, the free pneumatic hammers, and has for one of its end of the dog being bent at right angles, as objects a gradual admission of the motive at 4, and the screw-plug 5 and handle A hav- 75 z5 iiuid behind the piston or hammerduring poring a corresponding recess or seat for the retions of its return and forward strokes, whereception of the bent end of dog 4 when the dog by greater power is obtained and recoil obis in position to lock the parts together. viated. In carrying out this part of my in- B indicates the hammer-cylinder, provided vention I provide the piston with a supplewith a supply-port b and an exhaust-port b2, 8o

3o mental inlet or admission port so arranged, and in case a shouldered piston is used the as to admit motive duid .to the end of the bore of the cylinder is contracted between the piston before one-half of the return stroke of ports b and b2, as at 6, to receive that portion the piston is completed, and such a construcof the piston having the least diameter. tion embraces one feature of my invention. v@indicates a piston of diameters suitable to 85 In order to obtain the best results, I have iit the internal diameters of the cylinder B, found that the supplemental admission-port said piston having the channel or passage 7 should bear a relative proportion to the exand the ports 8 extending through its walls, haust-ports of about one to six or one to four, which port-s 8 are exhaust-ports and may also and such a construction embodies a further be supply-ports, according to the position of 9o 4o feature of my invention. There are other the piston (or hammer) within the cylinder minor features of invention, all as will hereand accordingly as they register with the supinafter more fully appear. ply-port b' or exhaust-port b2 of said cylinder.

I will now proceed to describe my invention In addition to said ports 8 8 I provide the by reference to the drawings, so that others piston with one or more supplemental supply 95 skilled in the art to which it appertains may or admission ports 9, so arranged therein as apply the same. to open or register with the supply-port of the In the drawings, A indicates the handle, B cylinder before one-half of the return stroke the cylinder, and C the piston, of a pneumatic of the piston has been effected, and such suphammer. The handle A has the motive-fluidplemental port or ports may be made directly roo 5o supply passage c, controlled by a suitable through the walls of the piston, as shown at throttle-valve T,-which is operated by means 9 in Fig. l of the drawings, or may be in the form of a groove orlohannel on the periphery of the piston, as indicated at 9 in Fig. 2 of the drawings, and in either case said supplemental port will not register with the supplyport of the cylinder until the main ports 8 are closedfas to the exhaust-port b2 of the cylin-` der, and therefore said supplemental ports 9 (or 9a) will never act as exhaust-ports.

The supplemental admission-port 9 (or 9a) should be of such size that it will not admit the motive fluid so rapidly as to arrest the motion of the piston before it has moved as far after said vport is opened as it had previously moved under the impulse due to the pressure of the motive duid at the other end of the piston-as, for instance, in the case of a shouldered piston such as shown in the drawings the port 9 (or 9a) should not be so large as to admit -sufcient pressure to counterbalance the pressure on the shoulderof the piston and arrest its movement before the piston-port 8 has registered with theinlet-port b' of the cylinder on the return stroke ofthe exceed the proportions of one (l) to four (4.)

The construction being substantiallysuch as hereinbefore pointed out, the operation of the machine will be as follows: The piston C being in the position shown in the drawings 1 and the throttle T having been opened 'to admit the motive iiuid to the cylinder, the m0- tive fiuid entering through port b will act upon the shoulder of the piston (or upon the corresponding piston-head) to cause the return stroke of the piston, andwhen the return movement of the piston has closed the ports 8 of the piston with relation to exhaust-port b2 of the cylinder the supplemental admission-port 9 (or 9, Fig. 2) will have opened to the supply-port b of the cylinder, vwhereupon fluid-pressure (dependent on the size of port 9 or 91) will be gradually admitted to the opposite end of the piston, the piston still continuing its returm movement, until sufficient pressure has been admitted through port-'9 to arrest the backward movement of the piston, which will then be reversed and make its lforward stroke. The small supplemental admission-port 9 (or 9a) will upon the reverse (or working) stroke of the piston supply the motive-duid pressure, which will thereafter follow up the piston and somewhat augment the force of the blow. The supplemental supply or admission port 9 (or 9a) will "be closed before the piston-ports 8 8 open to the exhaust-port b2 of the cylinder, so that the supplemental admission-port (9 or 9) never acts as an exhaust-port, though the main ports S 8 of the piston may, if desired, be arranged to serve alternately as supply and exhaust ports. Y

Among the advantages incident to my invention are simplicity of construction, effl-` ciency in operation, somewhat increased power, and the avoidance of objectionable recoil.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is-

l. The combination with a cylinder having supply and exhaust ports, of a piston having a supplemental supply-port so arranged with relation to the exhaust port or ports as to maintain a gradual ad mission of pressure over a large part of the return and forward strokes of .the piston, substantially as and for the purposes specified.

2. In a motive-fluid-operated tool, the combination with a cylinder having supply and exhaust ports,of -a-shouldered piston having admission and exhaust ports which control the admission-and-exhaust of thelinotive duid to the head of the piston above 'the shoulder one of said'portsfbeing an admission-port only, substantially as and for the purposes specified.

3. In a ymotive-fluid-operated tool, the combination `v with acylinder having supply and exhaust ports, of a shouldered piston having aplu rality of 'ports someof which are supply- Vports only and which control the admission ofthe motive fluid to Athe head of the piston above the shoulder while others are alternatel'y supply and lexhaust ports, substantially as and for 'the `purposes specified.

4. In a motive-Huid tool, the combination with a cylinder of a piston having a supplemental supply-port, admission and 4exhaust ports-controlling the admission and release of the motive fluid to and from the cylinder, the supplemental supply-port being of less than one-quarterthe cross area ofthe exhaustports, substantially as and for the "purposes specified.

5. In a motive-fluid tool, the combination -witha cylinder having supply and exhaust ports,of apiston having aplurality of ports, oneof which is a supply-port only, and which does vnot exceed one-fourth the cross area of the exhaust-ports, substantially as and for the purposes specified.

6. In a motive-uid-operated tool, the combination with acylinder, a cap for closing the end thereof, of a spring-dog adapted lto engage fthe screw-cap and provided with a free end which projects at an angle-to the dog, an annular screw-'plug for conining the springdog-said screw-plug having a slot or recess for receiving the bent free end of the dog, substantially as and for the purposes specified.

7. In a motive-fluid-operated tool, the combination with a cylinder, afcap for closing the end thereof, a handle having a ring or collar clamped between the flange of the screw-cap and the end of the cylinder, of a spring-dog adapted to engage the screw-cap and provided with a -free end which 'projects at an angle to the dog, an annular screw-plug for confining the spring-dog-said screw-plug and handle IOO IIO

having a slot or recess for receiving the bent free end of the dog, substantially as and for the purposes specified.

S. The 'combination With a cylinder having 5 supply and exhaust ports, of a piston having a supply-port arranged to gradually admit pressure over a large part of the return and forward strokes of the piston, and an exhaustport arranged to be opened by the movement l of the piston, substantially as and for the purio poses specified.

In testimony whereof I ax my signatur@ in presence of two witnesses, this 21st day of February, 1900.

CHARLES HARRIS J OHNSON; Witnesses:

H. H. VAUGHAN, GEORGE I. MCELDOWNEY.

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