Elongated-member-driving apparatus – Explosive-type driving means – With plunger
Reexamination Certificate
2000-02-08
2001-07-10
Smith, Scott A. (Department: 3721)
Elongated-member-driving apparatus
Explosive-type driving means
With plunger
Reexamination Certificate
active
06257476
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an explosive powder-actuated setting tool including a guide cylinder having an inner bore, a drive piston axially dispeaceable in the inner bore, a cartridge socket for receiving a cartridge and an inner diameter of which decreases in a setting direction of the setting tool, and a connection channel connecting the cartridge socket with the inner bore of the guide cylinder with the connection channel having a mouth opening adjoining the cartridge socket.
2. Description of the Prior Art
German Publication DE-0S 14 78 837 discloses a guide cylinder of a setting tool having a cartridge socket and an inner bore. A cartridge socket adjoins, at its end facing in the setting direction, the inner bore. The cartridge socket serves for receiving a propellant charge. A cylindrical connection channel extends between the cartridge socket and the inner bore. The diameter of the connection channel is smaller than the diameter of the cartridge socket. The connection channel has a mouth opening adjacent to the cartridge socket. The mouth opening widens in a direction toward the cartridge socket. The mouth opening is formed by a circular phase.
The setting tool disclosed in the German Publication does not allow for use of film cartridges because the film cartridge, upon the ignition of the propellant charge, would expand into the connection channel in a form of a spherical segment and, at some point, would explode. The remnants of the film cartridge would reach the inner bore and would contaminate it, adversely affecting future functioning of the setting tool.
Accordingly, an object of the present invention is to provide an explosive powder-actuated setting tool in which film cartridges filled with propellant charge can be used, without adversely affecting the subsequent functioning of the setting tool.
Another object of the present invention is to provide an explosive powder-actuated setting tool with means which would insure a simple and reliable ignition of the propellant charge filling a film cartridge.
SUMMARY OF THE INVENTION
These and other objects of the present invention, which will become apparent hereinafter, are achieved by providing an explosive powder-actuated setting tool in which the connection channel is formed of a first, sharp-edged circumferential section and a second circumferential section having a radius.
The first sharp-edged circumferential section provides for breaking down the film cartridge at a precisely defined location and an explosion of the film cartridge after a pressure necessary for complete combustion of the propellant charge has been attained. According to the invention, the second circumferential surface opposes the breaking of the film and insures that each film section which projects into the connection channel remains on the remnant portion of the film and does not reach the inner core of the guide cylinder.
In order to insure that the propellant charge pressure, which is generated upon ignition of the cartridge, reaches the inner bore of the guide cylinder through the connection channel unimpeded and that a connection region between the teared or torn film section and the remained portion of the film is as large as possible, preferably, the second circumferential section extends along maximum a half of an entire circumference of the mouth opening of the connection channel.
In order to insure that a portion of the foil, which projects into the connection channel, has a shape of a tongue with two, extending substantially parallel to each other, side edges and a semicircular end region, preferably, the first circumferential section is U-shaped, and the second circumferential section is linear.
In order to provide for an economical formation of the connection channel, a portion of the connection channel which adjoins the mouth opening and extends in the setting direction of the setting tool, has a cross-section that deviates from a circle.
The novel features of the present invention, which are considered as characteristic for the invention, are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its mode of operation, together with additional advantages and objects thereof, will be best understood from the following detailed description of preferred embodiments, when read with reference to the accompanying drawings.
REFERENCES:
patent: 3162123 (1964-12-01), Turner
patent: 3490673 (1970-01-01), Diehl
patent: 3709421 (1973-01-01), Kolmar
patent: 3851416 (1974-12-01), Engstrom et al.
patent: 4037770 (1977-07-01), Dorgnon et al.
patent: 4218005 (1980-08-01), Harris
patent: 4655380 (1987-04-01), Haytayan
patent: 5749509 (1998-05-01), Remeroski
patent: 5842623 (1998-12-01), Dippold
patent: 6062455 (2000-05-01), Giannuzzi et al.
patent: 1478837 (1969-03-01), None
patent: 2252177 (1975-06-01), None
patent: 9639281 (1996-12-01), None
Hilti Aktiengesellschaft
Sidley Austin Brown & Wood LLP
Smith Scott A.
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