US3061834A

US3061834A - Tool for removing signal bond terminals from rails

Info

Publication number: US3061834A
Application number: US125751A
Authority: US
Inventors: Temple Robert; Ernest E Temple
Original assignee: Mine Safety Appliances Co
Current assignee: MSA Safety Inc
Priority date: 1961-07-21
Filing date: 1961-07-21
Publication date: 1962-11-06
Anticipated expiration: 1979-11-06

Description

Nov. 6, 1962 R. TEMPLE ETAL TOOL FOR REMOVING SIGNAL BOND TERMINALS FROM RAILS Filed July 2l, 1961 477'0PA/Eys HH I La A mw RQ ...rvr

This invention relates to the removal of signal bond terminals from railroad rails, and more particularly to loosening such terminals by the use of explosive-actuated means.

Signal bonds are used for electrically connecting the adjoining ends of railroad rails so that the rails can serve as electrical conductors for the train signals along the track. Each bond consists of a short length of cable, the opposite ends of which are embedded in metal that lills metal cups which are forced into holes in the sides of the rails. The cups and their metal fillings and the ends of the cable embedded in them will be referred to herein as the terminals of the bond. For various reasons, including derailments and vandalism, the bond cables often are cut. To Yreplace them with new signal bonds, it first is necessary to remove the old terminals from the rails. This has always been a problem, because the terminals are very tightly wedged in the rails. The most common way of removing them has been to drill them out, which requires a considerable amount of time.

It is an object of this invention to provide a tool for removing rail bond terminals from rails extremely rapidly and with little effort.

In accordance with this invention, the tool preferably includes a clamp that can straddle the rail and engage its opposite sides. The side of the clamp adjacent the rail bond terminal that is to be removed from the rail has a transverse opening through it threaded at its outer end. The front end of a tubular housing is screwed into the opening. The rear end of the housing contains a breechblock. A stud-receiving barrel is slidably disposed in the housing and projects from it and through the clamp opening. When the clamp is applied to a rail, the barrel is moved rearwardly into contact with the breechblock. The housing also contains a coil spring, which is compressed by the barrel when the barrel is in its rear position. A firing pin in the outer end of the tool fires a stud-driving cartridge in the rear end of the barrel. When the tool is removed from the rail the barrel housing is unscrewed from the clamp and the barrel is pulled out of the front of the housing for reloading.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which* FIG. 1 is a plan view of our tool applied to a rail;

FIG. 2 is a vertical longitudinal section through the tool in operative position;

FIG. 3 is an enlarged fragmentary section showing a stud at the moment it strikes the inner end of the rail hole containing the signal -bond terminal; and

FIG. 4 is a fragmentary longitudinal section of the tool showing the position of the barrel in case the tool is assembled while not on a rail.

Referring to FIGS. 1 and 2 of the drawings, a signal bond has terminals 1 and 2 tightly embedded in two adjoining rails 3 and 4, respectively, provided with drilled holes for that purpose. Ordinarily, these two terminals are connected by a cable 5, but in this case the cable has been cut accidentally. To permit the terminals to be removed from the rails so that a new signal bond can be attached to them, ythe cable projecting from terminal 2 has been cut oil? approximately flush with the outer end of the cup as shown in FIG. 2, and the tool forming the subject of this invention has been applied to the rail.

Patented Nov. 6, 1962 Yice The main body of the tool is a `C-clarnp formed from a U-shape frame '7 that straddles rail 4 and is considerably longer than the width of the rail. One end of the frame is adapted to engage the side of the rail that contains the bond terminal 2 when a hand screw 8 in the opposite end of the frame is tightened against the adjacent side of the rail. The distance that the clamp extends down over the rail is controlled by a vertical hand screw 9 in the top of the frame, carrying at its lower end a plate 10 that rests on top of the rail. The rail-engaging end of the frame has an opening 11 through it that is centered around the bond terminal by sighting through the opening and adjusting the two hand screws accordingly. The outer end of the frame opening is enlarged and provided with screw threads 12, while the inner end is provided with an outwardly facing shoulder 13.

After the clamp has been applied in correct position on the rail, the threaded front end of a tubular housing 15 is screwed into clamp opening 11. A hollow breechblock 16, screwed into the rear end of the housing, contains a nut 17, in which a ring pin 18 is Slidably mounted. The point of the pin can project from the inner end of the breechblock. The rear end of the pin projects from the nut. Slidably mounted in the housing is a barrel 2li that has a cartridge chamber 21 in its rear end for receiving an explosive cartridge 22. The rear end of the barrel engages the breechblock and its front end is pressed against the rail around the bond terminal. A metal stud 23 forms the projectile and has a head 24 (FIG. 3) mounted in the front end of the cartridge. A short distance in front of the head the stud has an integral piston 25 that helps keep the stud centered in the barrel.

When the outer end of the firing pin is struck by a hammer, the cartridge is discharged and the explosion drives the stud forward through the barrel. It is a feature of this invention that the cartridge is powerful enough to drive the stud completely through the bond terminal and against the rail at the inner end of the hole containing the terminal, as shown in FIG. 3. This displaces the metal of the terminal and causes it to flow outward along the stud to such an extent that the terminal is loosened in the rail once in while. However, in order to be sure every time that the terminal can be extracted from the rail, a sufficient charge of powder is used in the cartridge to cause the stud to strike the rail hard enough to expand the front end of the stud slight. This enlargement 26 locks the terminal on the stud so that when the stud is pulled out of the rail by any suitable tool, the terminal will have to come out with the stud. The stud cannot pull out of the terminal. For an even better grip on the surrounding terminal, the stud can be knurled.

After the tool has been tired, the hand screw '8 of the clamp may be loosened to permit the tool to be removed from the rail, or barrel housing 15 may be unscrewed from the clamp first. The stud and terminal then are pulled out of the rail if they have not already fallen out. After the barrel housing has been removed from the clamp, barrel 20 can be pulled out of the front end of the housing, reloaded with a new stud and cartridge and then reinserted in the housing. When the barrel is inserted in the housing it will not engage the breechblock because its inward movement is stopped by a coil spring 27 at its inner end. Preferably, the inner end portion of the barrel is reduced to receive the spring and a sliding washer 28 that the spring presses against a radial shoulder 29 at the front end of the reduced portion. The surrounding portion of the barrel may be enlarged in order to form radial shoulder 301 that will limit forward movement of the washer and thereby retain the spring and washer in the housing while the barrel is removed. Since the coil spring spaces the rear end of the barrel from the inside of the sleeve.

lcause the loaded barrel is shown attached to the clamp before the clamp has lbeen applied to a rail. Nevertheless, since some people may assemble the tool while it is not on a rail, provision'ha's been made in such a case to prevent the barrel from sliding out of the front end of the barrel housing. Accordingly, the barrel is provided in front of the housing with an integral collar 32 that will engage shoulder 13 in the clamp opening 11 and thereby limit outward movement of the barrel.

While the barrel housing is separated from the clamp it is desirable to protect the housing threads. This can be done by a guard sleeve 34 encircling the housing and urged forward by a coil spring 35 encircling the housing The sleeve is provided with an interior shoulder 36 that engages the front of the spring, and the barrel housing is provided with a shoulder 37 engaging the rear end of the spring. While the barrel housing is screwed into the clamp as shown in the drawings, the front end of the sleeve is pressed against the clamp. When the housing is removed from the clamp, spring 35 pushes the sleeve forward over the housing threads until stopped by a pin 38 projecting from the housing into a longitudinal slot 39 in the sleeve.

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 vas specifically illustrated and described.

We claim:

1. A tool for driving a stud into a metal signal bond lterminal in a hole in one side of a rail, comprising a clamp adapted to straddle a rail and engage its opposite sides, one side of the clamp having a transverse opening therethrough threaded at its outer end, a tubular housing having a front end screwed into the outer end of said opening, a breechblock mounted in the rear end of the housing, a stud-receiving barrel slidably disposed in said housing and projecting therefrom through said clamp opening, the barrel being movable rearwardly in the housing into contact with the breechblock when the clamp is applied to a rail, a coil spring in said housing compressed by the barrel While the barrel is in its rear position, and a tiring pin for tiring a stud-driving cartridge in the rear end of the barrel.

2. A tool according to claim i, in which the projecting front end of the barrel has a shoulder and the inner end of the clamp opening reduced to form an interior shoulder engaged by the barrel shoulder to limit the distance said spring can push the barrel forward through the clamp.

3. A tool for driving a stud into a metal signal bond terminal in a hole in one side of a rail, comprising a clamp adapted to straddle a rail and engage its opposite sides, one side of the clamp having a transverse opening therethrough threaded at its outer end, a tubular housing having a threaded front end screwed into the outer end of said opening, a breechblock mounted in the rear end of the housing, a stud-receiving barrel slidably disposed in said housing and projecting therefrom through said clamp opening, the barrel being movable rearwardly into Contact with the breechblock when the clamp is applied to a rail, a coil spring in said housing compressed by the barrel while the barrel is in its rear position, a firing pin for rng a stud-driving cartridge in the rear end of the barrel, a guard sleeve encircling said housing and slidable thereon, a coil spring encircling the housing and pressing the front end of the sleeve against said clamp so that the sleeve will move forward around the threaded front end of the housing when the latter is removed from the clamp, and means operatively connected with the housing and sleeve for limiting the distance the sleeve can be moved forward on the housing.

References Cited in the le of this patent UNITED STATES PATENTS