US3893239A

US3893239A - Explosively actuated rail punch

Info

Publication number: US3893239A
Application number: US431219A
Authority: US
Inventors: Joseph L Giebel; Frank K Hill
Original assignee: Mine Safety Appliances Co
Current assignee: MSA Safety Inc
Priority date: 1974-01-07
Filing date: 1974-01-07
Publication date: 1975-07-08
Anticipated expiration: 1992-07-08

Abstract

A track rail having an upwardly tapered web portion is straddled by a yoke, one end of which carries a die with a substantially flat front face. The opposite end of the yoke carries explosively driven punching means in axial alignment with the die and also having a substantially flat front face lying in a plane perpendicular to the axis of the punching means. The front face of the die lies in a plane inclined to the plane just mentioned in order to provide a space between them tapering upwardly to substantially the same degree as the portion of the rail web that is to be punched. The yoke is clamped onto the rail with the top and bottom of the front face of the die engaging one side of the rail web so that the top and bottom of the front face of the punching means will strike the web at the same time when the punching means is driven forward.

Description

Giebel et al.

[ 1 EXPLOSIVELY ACTUATED RAIL PUNCH [75] Inventors: Joseph L. Giebel, Pittsburgh; Frank K. Hill, Irwin, both of Pa.

[73] Assignee: Mine Safety Appliances Company,

Pittsburgh, Pa.

[22] Filed: Jan. 7, 1974 [21] Appl. No.: 431,219

[52] 0.8. CI. 30/358; 30/361; 30/DIG. 4 [51] Int. Cl 1326f 1/00 [58] Field of Search 30/358, 361, DIG. 4

[56] References Cited UNITED STATES PATENTS 138,201 4/1873 Safely 30/361 667,258 2/1901 30/361 2,008,362 7/1935 Littlehale 30/358 UX 2,140,214 12/1938 Temple 30/358 UX 2,140,338 12/1938 2,302,646 11/1942 2,357,306 9/1944 Benner 30/36l July 8, 197 5 5 7 ABSTRACT A track rail having an upwardly tapered web portion is straddled by a yoke, one end of which carries a die with a substantially flat front face. The opposite end of the yoke carries explosively driven punching means in axial alignment with the die and also having a substantially flat front face lying in a plane perpendicular to the axis of the punching means. The front face of the die lies in a plane inclined to the plane just mentioned in order to provide a space between them tapering upwardly to substantially the same degree as the portion of the rail web that is to be punched. The yoke is clamped onto the rail with the top and bottom of the front face of the die engaging one side of the rail web so that the top and bottom of the front face of the punching means will strike the web at the same time when the punching means is driven forward.

4 Claims, 4 Drawing Figures PATENTEDJUL 8 I975 SHEET EXPLOSIVELY ACTUATED RAIL PUNCH Explosively actuated tools for punching holes in the webs of railroad track rails are known. Such a tool punches a hole having a center line perpendicular to the central vertical plane of the rail web. The punch strikes the rail web first at only one point. the lowest point of the punch. which causes the punch to tend to tilt by pivoting vertically on that point. The resulting internal stress on the punch and its driving piston is so great that it frequently results in failure of one or both of those components of the tool.

It is among the objects of this invention to provide an explosively actuated rail punching tool. which does not tend to tilt the punch during punching. which protects the operator from possible injury. which has a longer life than similar tools known heretofore and which requires less power to operate.

The preferred embodiment of the invention is illustrated in the accompanying drawings. in which FIG. I is a side view. with parts broken away in sec tion. showing the tool mounted on a rail;

FIG. 2 is a view of the front end of the die taken on the line ll-ll of FIG. 1;

FIG. 3 is a vertical section taken on the line Ill-lll of FIG. I; and

FIG. 4 is a view of the right-hand end of the tool as seen in FIG. 1, the rail not being shown in FIGSv 2, 3 and 4.

Referring to FIG. 1 of the drawings, a typical railroad track rail is shown which has a head 1 and a foot 2 integrally connected by a vertical web 3. The web shown is not of uniform thickness from near its top to near its bottom. but has slightly concave sides. Also, the contour of the web is such that the portion of it that is to be punched is thinner at its top than at its bottom. so that portion is referred to herein and in the claims as being tapered upwardly. whether its opposite sides are flat or slightly curved as shown. It is this taper that causes the problem that this invention solves.

Clamped onto this rail is a tool for punching holes through the upwardly tapered portion of the web. Such holes can be used for bolts for connecting splice plates to the rail in a well-known manner. The punching tool includes a U-shaped yoke S that straddles the rail. The upper part of the yoke rests on the rail head and its opposite ends extend down beside the opposite sides of the web. The lower ends of the yoke are provided with axially aligned passages 6 and 7 through them. One of these passages normally contains punching means formed from a piston 8 slidably mounted in the passage and having a socket in its front end in which the rear end portion of a punch 9 has a sliding fit. The opposite end ofthe piston has a tapered portion that has a wedge fit in a socket 10 in the inner end ofa plug 11 screwed into the outer end of passage 6. This plug has an axial bore through it that forms a chamber for an explosive cartridge 12. Screwed onto the reduced outer end of the plug is a breech block 14 provided with an axial bore containing a firing pin 15 that is urged forward by a coil spring [6. The firing pin can be retracted by a pull ring 17 in its outer end so that a U-shaped spacer 18 can be inserted between a collar 19 on the outer end of the firing pin and the breech block. As shown in FIGS. 1 and 4, a safety pin 20 in the spacer prevents it from being removed accidentally. When this pin is removed, the spacer can be pulled away, which will allow the spring to drive the firing pin forward against the cartridge to detonate it. This will drive the piston and punch forward toward the rail.

At the front end of yoke passage 6, which is the end adjacent the rail. the yoke is provided at opposite sides of the passage with integral portions 22 projecting under the rail head into engagement with the rail web. The ends of these projecting portions preferably are convex. As shown in FIG. 3, the inner surfaces of the projecting portions 22 are curved on the same radius as passage 6 in order to fit opposite sides of the piston when it is driven forward out of the passage and thus help to guide it.

The passage 7 through the opposite end of the yoke is threaded and a threaded stud 23 is rotatably mounted in it and provided in its outer end with a socket 24 for a wrench. The front end of this member projects from the yoke toward the rail and extends into a shallow socket 25 in the rear end of a hollow die 26. This die extends from the stud to the rail web when the tool is clamped in place. which is done by turning the stud to press the die against the rail and simultaneously draw the projecting portions 22 of the yoke against the opposite side of the rail web. The die is prevented from turning on its axis when the stud is turned. because the top of the die is provided with a flat surface that engages an overhanging flat surface 27 of the yoke as shown in FIGS. 1 and 2. The inside of the die is a size to receive the punch and the slug that it punches out of the rail.

It is a feature of this invention that during the punching operation lateral or off-center stress on the punch and piston is avoided. Accordingly. the front end of the die is substantially flat and lies in a plane inclined to the axis of the die and also to the plane of the front face of the punch. which may be provided with a forwardly projecting central point if desired. The plane of the front face of the punch is perpendicular to the axis of the punch and piston. and the inclination of the two planes just mentioned is such that the space between them tapers upwardly to substantially the same degree as the portion of the rail web between them. Consequently. as the yoke is being clamped onto the rail as previously described. the yoke will rock on the rail until the top and bottom of the front end of the die engage the web, whereupon the front face of the punch will be generally parallel to the side of the web directly in front of it. When the tool is fired. the top and bottom of the punch will strike the rail web at the same time so that no torque is exerted on the punch which might cause it to break away one side of the piston socket. The top and bottom of the flat front end of the piston also will strike against the rail web simultaneously, which will arrest the piston. There will be no lateral strain on the punch and piston as there has been before.

The punch, due to inertia, will leave the piston socket and will pass entirely through the rail and into the hollow die along with the slug that it punches out of the rail. After the tool has been released from the rail by backing off stud 23, the die can be slipped off the end of the stud 23 and the slug and punch dropped out of the die. Then the punch can be inserted again in the socket in the front end of the piston for the next punching operation. The axis of the hole punched in the rail will be inclined a few degrees to the central vertical plane of the rail, but that makes no difference because the bolt that is used is enough smaller than the hole to permit the bolt to be disposed horizontally.

As a safety precaution, to protect the operator from any fragments of metal that might fly away from the rail during the punching operation. it is desirable to provide the tool with a guard. Such a guard may have parallel sides connected by a flat bottom close to the bottom of the yoke beneath the punch as shown in F165. 1 to 3. The sides of the guard extend up the opposite sides of the yoke and their upper edges are turned toward each other to provide narrow flanges 31 supported by short pins 32 projecting from the sides of the yoke. The outer end of the guard is closed by an end plate 33 pro vided with a central opening. through which the outer end of plug 11 extends. When the breech block is screwed onto the plug. it forces the guard forward to press its front end against the web ofthe rail. When the breech block is removed for reloading the tool. the guard is prevented from accidentally moving outwardly far enough to fall off the yoke by means of a stop pin 34 projecting inwardly from one side of the guard at its front end. This pin will strike one of the supporting pins 32 for the guard and thereby limit outward movement of the guard.

The tool is provided with a handle that preferably in' cludes a U-shaped bracket 35 seated on top of the yoke and having ears 36 extending downwardly in engagement with opposite sides of the yoke. Screws 37 extend through these ears into the yoke to hold the bracket firmly in place. The upper part of the bracket is provided with aligned holes in which the opposite ends of a tube 38 are welded. This tube forms a hand grip. In case two men want to carry the yoke. a short pipe or rod 39 can be inserted in the tube. with the ends of the rod projecting from it. To center the rod in the tube. the rod may be provided with a cross pin 40 that will engage one end of the tube.

It will be seen that the punching tool disclosed herein operates in a straight line with no forces acting on any of its parts during punching that would impart lateral strain on them. so the tool has a longer life and needs less power to operate. This is especially true when heavy rails. such as 140 pound rails. are being punched. The guard is locked in place when the tool is mounted on a rail and therefore the guard must be used in all punching operations.

According to the provisions of the patent statutes. we have explained the principle of our invention and have illustrated and described what we now consider to represent its best embodiment. However. we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

We claim:

1. A tool for punching an inclined hole through the upwardly tapered portion of the web of a track rail. comprising a yoke adapted to straddle the rail and having ends for extending down beside its opposite sides. a hollow die between said ends carried by one of them and having a substantially flat front face. explosively driven punching means carried by the opposite end of the yoke in axial alignment with the die and having a substantially flat front face lying in a plane perpendicular to the axis of the punching means. the front face of the die lying in a plane inclined to said first-mentioned plane to provide a space between said planes tapering upwardly to substantially the same degree as the portion of the rail web that is to be punched, and a threaded member screwed into said one end of the yoke and having a projecting inner end engaging and supporting said die. said member being rotatable to move the die toward the punch for clamping the yoke onto a rail with the top and bottom of the inclined front face of the die engaging one side of the rail web. and the yoke and die having engaging surfaces that prevent rotation of the die when said threaded member is turned. whereby the top and bottom of the front face of the punching means will strike the web at the same time when the punching means is driven forward.

2. A tool for punching an inclined hole through the upwardly tapered portion of the web of a track rail. comprising a yoke adapted to straddle the rail and hav ing ends for extending down beside its opposite sides. a hollow die between said ends carried by one of them and having a substantially flat front face. explosively driven punching means carried by the opposite end of the yoke in axial alignment with the die and having a substantially flat front face lying in a plane perpendicular to the axis of the punching means. the front face of the die lying in a plane inclined to said first-mentioned plane to provide a space between said planes tapering upwardly to substantially the same degree as the portion of the rail web that is to be punched. said opposite end of the yoke having a portion projecting toward said one end of the yoke for engaging a rail web when the yoke is clamped onto it. means for clamping the yoke onto a rail with the top and bottom of the inclined front face ofthe die engaging one side of the rail web so that the top and bottom of the front face of the punching means will strike the web at the same time when the punching means is driven forward. a guard straddling said opposite end of the yoke and having two side walls and a bottom wall. the guard being movable forward from a rear inoperative position to a forward guarding position beside said projecting portion of the yoke. 21 cartridge-receiving member carried by the rear end of said opposite end of the yoke, a firing pin behind said member, and a breech block carrying the firing pin and adjustable forward relative to said member to move said pin from a rear inoperative position to a forward operative position, the breech block being engageable with said guard to move the guard forward to its guarding position when the breech block is adjusted forward to the operative position of the firing pin. whereby the tool cannot be operated until the guard is in its guarding position.

3. A tool for punching an inclined hole through the upwardly tapered portion of the web of a track rail. comprising a yoke adapted to straddle the rail and having ends for extending down beside its opposite sides. a hollow die between said ends carried by one of them and having a substantially flat front face, explosively driven punching means carried by the opposite end of the yoke in axial alignment with the die and having a substantially flat front face lying in a plane perpendicular to the axis of the punching means, the front face of the die lying in a plane inclined to said first-mentioned plane to provide a space between said planes tapering upwardly to substantially the same degree as the portion of the rail web that is to be punched, and means for clamping the yoke onto a rail with the top and bottom of the inclined front face of the die engaging one side of the rail web, whereby the top and bottom of the front face of the punching means will strike the web at the same time when the punching means is driven forward, said punching means including a piston and a the inner surfaces of said projecting portions forming continuations of the wall of said passage to guide the piston when it is driven forward.

4. A tool according to claim 3. including a guard extending forward from said opposite end of the yoke to the front end of said projecting portions.

Claims

1. A tool for punching an inclined hole through the upwardly tapered portion of the web of a track rail, comprising a yoke adapted to straddle the rail and having ends for extending down beside its opposite sides, a hollow die between said ends carried by one of them and having a substantially flat front face, explosively driven punching means carried by the opposite end of the yoke in axial alignment with the die and having a substantially flat front face lying in a plane perpendicular to the axis of the punching means, the front face of the die lying in a plane inclined to said first-mentioned plane to provide a space between said planes tapering upwardly to substantially the same degree as thE portion of the rail web that is to be punched, and a threaded member screwed into said one end of the yoke and having a projecting inner end engaging and supporting said die, said member being rotatable to move the die toward the punch for clamping the yoke onto a rail with the top and bottom of the inclined front face of the die engaging one side of the rail web, and the yoke and die having engaging surfaces that prevent rotation of the die when said threaded member is turned, whereby the top and bottom of the front face of the punching means will strike the web at the same time when the punching means is driven forward.

2. A tool for punching an inclined hole through the upwardly tapered portion of the web of a track rail, comprising a yoke adapted to straddle the rail and having ends for extending down beside its opposite sides, a hollow die between said ends carried by one of them and having a substantially flat front face, explosively driven punching means carried by the opposite end of the yoke in axial alignment with the die and having a substantially flat front face lying in a plane perpendicular to the axis of the punching means, the front face of the die lying in a plane inclined to said first-mentioned plane to provide a space between said planes tapering upwardly to substantially the same degree as the portion of the rail web that is to be punched, said opposite end of the yoke having a portion projecting toward said one end of the yoke for engaging a rail web when the yoke is clamped onto it, means for clamping the yoke onto a rail with the top and bottom of the inclined front face of the die engaging one side of the rail web so that the top and bottom of the front face of the punching means will strike the web at the same time when the punching means is driven forward, a guard straddling said opposite end of the yoke and having two side walls and a bottom wall, the guard being movable forward from a rear inoperative position to a forward guarding position beside said projecting portion of the yoke, a cartridge-receiving member carried by the rear end of said opposite end of the yoke, a firing pin behind said member, and a breech block carrying the firing pin and adjustable forward relative to said member to move said pin from a rear inoperative position to a forward operative position, the breech block being engageable with said guard to move the guard forward to its guarding position when the breech block is adjusted forward to the operative position of the firing pin, whereby the tool cannot be operated until the guard is in its guarding position.

3. A tool for punching an inclined hole through the upwardly tapered portion of the web of a track rail, comprising a yoke adapted to straddle the rail and having ends for extending down beside its opposite sides, a hollow die between said ends carried by one of them and having a substantially flat front face, explosively driven punching means carried by the opposite end of the yoke in axial alignment with the die and having a substantially flat front face lying in a plane perpendicular to the axis of the punching means, the front face of the die lying in a plane inclined to said first-mentioned plane to provide a space between said planes tapering upwardly to substantially the same degree as the portion of the rail web that is to be punched, and means for clamping the yoke onto a rail with the top and bottom of the inclined front face of the die engaging one side of the rail web, whereby the top and bottom of the front face of the punching means will strike the web at the same time when the punching means is driven forward, said punching means including a piston and a punch carried by the front end of the piston, the front face of the piston being parallel to the front face of the punch, said opposite end of the yoke being provided with a passage therethrough containing said piston, said opposite end of the yoke also having portions at opposite sides of said passage projecting toward said die for engaging a rail web when the yoke is clamped onto it, the inner surfaces of said projecting portions forming continuations of the wall of said passage to guide the piston when it is driven forward.

4. A tool according to claim 3, including a guard extending forward from said opposite end of the yoke to the front end of said projecting portions.