US1863390A

US1863390A - Electric discharge device

Info

Publication number: US1863390A
Application number: US328739A
Authority: US
Inventors: Frank R Beckert
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1928-12-27
Filing date: 1928-12-27
Publication date: 1932-06-14
Anticipated expiration: 1949-06-14

Description

June 14, 1932.

F.R.BECKERT Filed Dec.

ELECTRIC DI SCHARGE DEVICE Inventor Frank R. Beckert,

BWwZZaM H'Ls Attorney.

Patented June 14, 1932 UNITED STATES PATENT OFFICE FRANK R. BECKERT, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK ELECTRIC DISCHARGE nnvrcn Application filed December 27, 1928. Serial No. 328,739.

My invention relates to electric discharge devices such as mercury arc rectifiers for example, and has for its principal object the provision of an improved resilient and con- 6 ductive lead-in conductor for such devices.

In mercury arc rectifiers, it issometimes desirable to use grid or control electrodes for controlling the current flow from each anode and for protecting the anodes from arc-back during the negative half cycle of the potential applied to the rectifier. The control electrodes are of various forms but must be insulated in each instance from the conductive walls of the rectifier, and must be mounted near the end of the anodes. The anodes are mounted within sleeves to protect them from mercury particles emitted from the cathode, and the control electrodes are therefore, also mounted within the sleeves. Because of this mounting the electrodes are inaccessible and it is difficult to attach to them a lead-in conductor which must necessarily be attached after the electrode is mounted within the anode sleeve. The lead-in conductor projects through and is insulatingly sealed to the wall of the rectifier by means of a vitreous material such as glass.

It has been customary to thread the leadin conductor into a tapped hole in the wall of the electrode. This method has the disadvantage that it is difficult to thread the con ductor into this hole and due to the unequal expansion of the walls of the rectifier and the lead-in conductor, the conductor seals were quite often broken.

In accordance with my invention these difficulties are overcome by providing a resilient and conductive member supported by the grid or control electrode and arranged to engage the lead-in conductor.

My invention will be better understood from the following description when considered in connection with the accompanying drawing and its scope will be pointed out in the appended claims.

Referrln to the drawing, Fig. 1 illustrates a section of a mercury arc rectifier illustrating one of the anodes, control electrodes and the lead-in conductor attached to the latter in accordance with my invention. Figs. 2 and 3 illustrate details of the lead-in conductor and its connection to the electrodes and Fig. 4 illustrates a modification of my invention.

Fig. 1 illustrates a section of a rectifier casing 10, a sleeve 11 attached thereto and forun 1ng a recess for'the anode 12. A sleeve 13 pro ecting into the tank 10 is mounted at the lower end of sleeve 11 and supports funnel shaped bafile or nozzle 14 which directs the rectifying arc toward the tip of the anode 12. A control electrode 15 comprising a metallic sleeve 16 having a wire screen 17 across its end is supported by an insulator 18 within the sleeve 11 directly below the anode 12. i

A lead-in conductor 19 surrounded by an insulating sleeve 20 projects through a metall1c sleeve 21 attached to and projecting through the wall of cylinder 11 and a casing 22. The casing 22 surrounds tank 10 and forms a water jacket about the tank through which cooling water is circulated during the operation of the rectifier.

The lead-in conductor 19 terminates in a member 23 which is sealed by means of a glass seal 24 to a member 25. The member 25 is in turn attached to the sleeve 21 by means of a member 26. The aluminum wire gasket 27 provides a vacuum tight joint between these two members.

It is evident that the electrode 15 is quite inaccessible and. that it is difiicult'to obtain a good conductive connection between it and the lead-in conductor. I have therefore in accordance with my invention provided a cup shaped member 28 which is attached to the electrode 15 and supports a coil spring 29. The spring 29 is a. helical coil of sufficient length and diameter so that when it is coiled within the cup 28 the circle formed by the inner extremities of its turns is slightly smaller than the diameter of the lead-in conductor 19. The member 28 is welded or otherwise attached to the control electrode 15 and its walls are turned in after spring 29 is 9 placed therein so that the latter is held in place within the cup.

When assembling the rectifier the electrode 15 is placed so that member 28 will line up with sleeve 21 with only a fair degree of accurac The lead 19 is then simply inserted into t e sleeve 21 and ushed down until its lower end is gripped y the resilient turns of the spring 29. The resiliency of the spring and the diameter of the turns thereof provide or within the rectifier tank, and to complete the seal after it has been so mounted. For

such instances I have modified my invention as illustrated in Fig. 4. The resilient connection in this construction is made between the terminal member 30 and the lead 31. Lead 31 is a straight conductor threaded into the electrode sleeve 16 and extending back into the member 30. Member 30 corresponds to a combination of the

members

23 and 28 of Fig. 1 and the spring 29 is held therein as in part 28.

The conductor 31 is made long enough so that it extends past the spring 29 and may freely expand or contract without interfering with its contact between the spring and itself and without injury to the glass seal 24. V

What I claim as new and desire to secure by Letters Patent of the United States, is:

1. An electric discharge device provided with an electrode mounted within an evacuated vessel, a sleeve connected to a wall of said vessel and projectin outwardly thereof, a terminal supported by and insulated from saidsleeve, a connection including a rigid member and a helical spring interposed between said electrode and said terminal, said sleeve enclosing a portion of said rigid memher, and a cup-shaped member mounted upon said electrode for supporting said spring.

2. An electric discharge device provided spring closely adjacent said electrode and in electrical connection therewith, and means including a tubular member connected to said vessel and enclosin a portion of said rigid member to guide said rigid member into engagement with said spring.

In witness whereof, I have hereunto set my hand this 26th da of December, 1928.

I RANK R. BECKERT.

with an electrode mounted within an evacu- Y ated vessel, a terminal insulated from said vessel, a connection including a resilient member and a rigid member adapted slidably to engage said resilient member, said connection being interposed between said electrode and said terminal, means to mount said resilient member upon said electrode, and means including a sleeve connected to said vessel and enclosing a portion of said rigid member to guide said rigid member into engagement with said resilient member.

3. An electric discharge device provided with an electrode mounted within an evacuated vessel, a terminal insulated from said vessel, a connection including a helical spring and a rigid member adapted slidably to engage said helical spring, said connection being interposed between said electrode and said terminal, means to mount said helical