US 1865637 A
Description (OCR text may contain errors)
E. B. LEAR STEEL RETAINER Filed March 17.
Patented July 5, 1932 UNITED STATES PATENT OFFICE EARL IB. LEAR, or gHILLIPSBURG, NEW JERSEY, ASsIGEoR TO INGERSQLL-RAND com- PANY, or JERSEY CITY, N W JERSEY, A CORPORATION on NEW JERSEY STEEL RETAINER Application filed March 17, 1931. Serial H0. 523,283.
threads 22 in the barrel 12. A shoulder 30- M This invention relates to pneumatic tools, but more particularly to steel retainers for pneumatic tools.
It is an object of this invention to enable 6 the working implement to be held securely in position during the operation of the tool.
Another object is to permit rapid exchange of working implements by the tool operator.
Still another object is to enable the construction of a locking clip for the steel retainer in which accidental removal by earth or rock dust working under the tongue ofthe locking clip is prevented.
Other objects will be in part obvious and in part pointed out hereinafter. All of these objects are obtained by the device shown in the accompanying drawing, in which Figure 1 shows a sectional view of the front end of a coal pick.
Figure 2 is a cross sectional view of Figure 1 taken on the line 22 looking in the di-- rection indicated by the arrows.
Figure 3 is a view of the front portion of the front head showing the steel retainer and locking clip in place, and
Figure 4 is a perspective view of the looking clip.
Referring more particularly to the draw-- ing, 10 designates a coal pick having a cylinder 12 in which is mounted a reciprocating piston 14. An enlarged bore 16 in the forward portion of the cylinder 12 is adapted to receive the collar 18 of a working implement 20.
As is well known in the art it is necessary to provide a means of keeping the working implement 20 in the bore 16 and in operating position. If the working implement is not securely held in place the pneumatic hammer becomes a dangerous instrument due to the fact that the working implement may be shot from the barrel with great force under the blows of the piston.
In the device of the present application, discharge of the working implement 20 is prevented in the following manner.
The forward portion of the bore 16 is threaded as shown at 22, a front head 24 havin a reduced portion 26 is threaded externally at 28 to cooperate with the interior -formed on the front head abuts snugly against the end 32 of the barrel 16. A bore 34 is formed throughout the length of the front head to be screwed firmly into place by means of an ordinary monkey wrench.
Slots 38 are formed in the front head. A
groove 40 is formed in the front end of the barrel 16 and slots 42 are. formed in the raised bead between the slot 40 at the end 32 of the barrel 16.- U i The operation of the tool retainer is as follows: A: tool 20, having a collar 18, is placedlin the barrel 16 of the tool 10. .The front head24 is then slipped over the end of the working implement 20 and the threads 28 on the front head brought into engagement with the threads 22 in the barrel 16. The threaded portions are firmly screwed together by means of a wrench, The front head must now be prevented from unscrewing under the vibration of the piston of the working implement. To this end a number of slots 38 are formed in the front head and in the forward part of the cylinder a number of slots areformed which number exceeds the number in the front head by one. It will be noted that it is. almost impossible toscrew the front head 24 onto the cylinder, without having one of the slots on the front head in registry with one of the slots on the cylinder. In order to prevent rotational movement of the front head with respect to the barrel of;
the tool a split ring 44 having a tongue 46 and a turned up portion 48 is snapped into the groove 40 so that the tongue 46 lies in the pair of slots 88 and 42 which are in re 'istr thus effectivel reventin unscrewa: y y p g ing of the front head 24. The novel manner in which dirt is prevented from entering the slots 38 and passing under the tongue 46 is shown in Figures 1 and 3. A raised bead 50 which passes completely around the front head 24 effectively forces soil, rock dust, coal dust or any other material, outward, away from the tongue 46 and thus prevents dirt being wedged under the tongue with the corresponding loosening of the spring ring 44:.
When it is desired to change the working implement, a screw driver or some sharp instrument can be thrust under the up-turned portion 48 of the spring ring 44: and the tongue 46 permitted to rest upon one of the raised portions 43 of the cylinder. 'lhefront head 24 may then be unscrewed and the Working implement removed.
I claim: I 1
l. A steel retainer for pneumatic tools, comprising a front head, a threaded portion on the front head cooperating with a threaded portion on the cylinder of the pneumatic tool,
a bore in the front head adapted to permit the passage of the shank of the working implement, a collar on the Working implement larger than the bore in the front head, a plurality of slots in the front head parallel to the axis of the tool, a plurality of slots in the cylinder to register with the first said slots and exceeding by one the number of slots in the front head, and a spring ring having an integral tongue adapted to lie, in a pair of registering slots. 7
2. A steel retainer for pneumatic tools, comprising a front head, a threaded portion on the front head cooperating with a threaded portion on the cylinder of the pneumatic tool, a bore in the front head adapted to permit the passage of the shank of the working implement, a collar on the working implement larger than the bore in the front head, a plurality of slots in the front head parallel tothe axis of the tool, a plurality of slots in the cylinder exceeding by one the number specification.
of slots in the front head, a spring ring having a tongue adapted to lie in a pair of slots,
one of the slots being on the front head and one of the slots beingon the cylindersaid slots being in registry, and a bead formed around the front head forwardly of the slots and the tongue to prevent the lodgement of foreign matter under the tongue.
In testimony whereof I have signed this EARL B. LEAR.