US2657284A

US2657284A - Trolley wire contact device

Info

Publication number: US2657284A
Application number: US290894A
Authority: US
Inventors: John L Mcglothlen
Original assignee: MARTIN HARDSOCG CO
Current assignee: MARTIN HARDSOCG CO
Priority date: 1952-05-31
Filing date: 1952-05-31
Publication date: 1953-10-27
Anticipated expiration: 1970-10-27

Description

Oct. 27, 1953 McGLQTHLEN 2,657,284

TRQLLEY WIRE GONTACT DEVICE Filed May 31, 1952 2 Sheets-Sheet l IN V EN TOR.

JOHN L. McGLOTHLEN.

ATTORNEYS.

Oct. 27, 1953 J MQGLQTHLEN 2,657,284

TROLL-BY WIRE CONTACT DEVICE Filed May 31, 1952 2 Sheets-Sheet 2 ATTGRNEY5.

INVENTOR. JOHN L. McGLOTHLEN.

Patented Oct. 27, 1953 TROLLEY WIRE CONTACT DEVICE John L. McGlothlen, Pittsburgh, Pa., assignor to The Martin Hardsocg 00., Pittsburgh, Pa., a corporation of Pennsylvania Application May 31, 1952, SerialNo. 290,894.

16 Claims.

This, invention relates to an electrical connector, and more particularly, to an improved con.- nector for making adetaohable electrical connection to a source of electrical potential such as a trolley wire or the like.

In single wire systems, such as trolley wires, the electrical energy is transmitted over a. bare conductor which is operative to supply electrical energy to apparatus having one terminal connected to the Wire. and the other to the ground. It frequently is desirable to make a connection to the trolley wire for operating auxiliary apparatus adjacent the trackway over which the trolley wire is located. The conventional manner of making such connections is to provide a terminal connector having a hook or clamp which is placed. in direct engagement with the trolley wire to make the connection. One disadvantage of conventional connectors. is that they must be removed to permit a. trolley to pass by without becoming disconnected from the trolley wire. Another and. more serious disadvantage of conventional connectors is. that they introduce a considerable element or danger to the workmen making a connection. Thisdanger is due to the possibility oi. leakage conducting paths being created through whichvthe trolley wire may be connected through the workman to, ground, thereby resulting in injury and sometimes death to the workman. Such leakage paths are most com.-

monly due to the accumulation, of. dirt on the One of the principal objects of this invention is to provide a connector for making a connection to a trolley wire which is operable to eliminate the danger of grounding the trolley wire through the. workman. making. the connection. end, there is provided a connector having. an insulating handle andv a contact which is movable by manipulation of the handle to make a connection with a stationary contact in electrical,

conducting engagement with the trolley wire. The, handle is provided with a conducting element projecting outwardly therefromfor engagement with a grounding element. The conducting elementv is. sov arranged that it will engage with.

the. grounding element to place the handle at ground. potential prior to. the establishment of a To this.

2; connection through the contact carried by the handle. In. this. manner, there is established a direct connection of the handle to ground, thereby preventing grounding of the trolley wire through the workman. andthus. preventing injury to the workman.

Another object of this invention is to provide a connector for making an electrical, connection of auxiliary apparatus to a trolley wire which will not interfere with the movement of the trolley along the wire andby the connection.

This application is a continuation-in-part of my application Serial No. 38,489, filed July 13, l943, for Trolley Wire Contact Device, now abandoned. One or themain uses of the trolley wire connector of the type shown in application Serial No. 38,489 is inundergroundmining, particularly coal mining. Practically all coal mining operations are carried on with electrical equipment, and the electrical current is distributed. through the mine by trolley wires. Some machines and tools, such as power coal cutting machines, drills and loading machines, are portable and are moved about in the mine entries and rooms asv they are extended. Since these machines perform heavy service, high electrical amperage current, is required so. that good contactsand safe connections are required. Further underground mining creates much dust and dirt and f n water is p esen n. h wa -k ler ,v Q that it is. important to. have connections with h tr lley W lIe at will. not be short-circuited to. the ground by the accumulation of dust and moisture.

Accordingly, a further object of; the invention is: to provide a trolley wiresupport on which a connector may be. mounted; to make a good electrical: connection with, the trolley wire.

A still further object of the. invention is to provide a connector by which a good electrical connection may be made with a trolley, and the connection mechanism shielded to prevent shortcircuiting and a connection with ground of a person handling the connector.

Other objects and advantages. of the inven tion will become apparent from the following description.

In the drawings, there is shown a preferred embodiment. of the invention. In this showing:

Fig. 1 is a side elevational view or a connector constructed in accordance with the principles of thi invention, a part of the apparatus, to. which it is. connected being broken, away and. shown in section;

Fig. 2 is an end view of the structure shown in 1;

Fig. 3 is a longitudinal sectional view of the connector shown in 1 and 2;

Fig. 4. is a bottom plan view of a modified form of trolley wire support in which a trolley connector may be mounted to make an electrical connection at each side of the trolley wire;

Fig. is a vertical sectional View taken on the line V-V of Fig. 6 of an improved trolley wire support showing in section a trolley connector mounted therein;

Fig. 6 is a sectional view of the trolley wire support taken on the line VI--VI of Fig. 5;

Fig. 7 is a view in side elevation of the preferred form of trolley connector;

Fig. 8 is a bottom plan view of a portion of the trolley connector shown in Fig. 7; and

Fig. 9 is a vertical sectional view of the trolley connector taken on the line IX-4X of Fig. 8.

Referring to Figs. 1 and 2 of the drawings, the numeral l designates a trolley wire which is carriecl by clamping members 2 having a nut 3 and bolt 4 for holding them in clamping engagement with the wire l as indicated. The clamping members 2 are secured to and supported by insulation 5 bonded to a supporting housing 6 which is formed of metal. A threaded mounting memher i is connected to the upper part of the housing 6 to provide a connection by which the entire structure may be secured to a support. As illustrated, the mounting member i is secured to a wood plug 8 which is adapted to be driven into an opening formed in the roof of a mine. When the roof of a mine is not solid, a hole is drilled therein for the reception of the plug 8 into which the fastening member 1 is threaded, the fastening member I being provided with threads (not shown) at its upper end. Where the roof of a mine is solid, it is not necessary to employ the wood plug it and a metal support for threaded engagement with the member I may be employed in accordance with conventional practice. The parts thus far described comprise a conventional support for an underground trolley wire and form no part, per se, of this invention.

Since in ordinary usage, the plug 8 would operate to insulate the member I and housing 6 from ground, a copper wire or strip 9 is secured to the outer surface of the plug and has a part thereof in electrical engagement with the member i as at 9. In this manner the strip 9 will be in tight engagement with the roof structure of the mine when the plug is mounted in position and will be effective to provide a ground connection for the housing 6 for a purpose to be described. Obviously, the copper strip 9 is not necessary where a metal anchor for the member I is provided in place of the plug 8.

The connector for making an auxiliary connection to the trolley wire I is indicated as a whole by the numeral l0 and is provided with an elongated body H formed of insulating material which provides a handle by which the connector may be manipulated when making a connection. As best shown in Fig. 3, the body member ll is hollow and is provided with an opening l2 for the reception of an insulated conduit l3 by which the power may be fed from the trolley wire to the auxiliary apparatus. The inner terminal end of the conduit [3 is connected to a conductor strap M which is secured in position on an insulating support which is preferably molded from suitable insulating material. A conductor strap I6 is mounted on the support I5 at a point spaced from the strap I4 and is connected with a part I! projecting outwardly through an opening in the insulation IS. The part I! is bent at right angles to the strap I6 and provides a movable contact for a purpose to be described. The conductor straps I t and i5 are provided with conducting clamps ii! for engagement with the ends of a fuse I!) which provides a protective connection between straps l4 and IS. The housing H is provided with a threaded connection to the body of the insulating support l5 and a screw 20 is provided for pre Venting rotation of the housing I l on its support l5. An annular flange 2i is provided on the insulating support l5 at the inner end of the han dle on housing II to prevent accidental contact with the movable contact 11.

A grounding element 22 in the shape of a rod formed of conducting material has its inner end secured in the insulating material of the support 15. The rod 22 extends outwardly from an opposite side of the flange 2| with respect to the handle II and is operable to place the handle H at ground potential in a manner to be described.

A grounding element comprising a cylinder 23 formed of metal is clamped in position on the housing 6. The cylinder 23 is in contacting engagement with the surface of the housing 6 and is thus connected to ground through the housing 6 and mounting member I.

The clamping members 2 have a conductor strap 24 secured thereto as by welding. The conductor strap is provided with a pair of contact elements 25 at its outer end to provide a notch for the reception of the movable contact [1.

The above described arrangement of the grounding element or cylinder 23 and strap 24 illustrates the present preferred embodiment of the invention. By this arrangement, trolley wire insulating supports already in position may be readily adapted for use with the connector it. To do so, it is merely necessary to clamp the cylinder 23 in position on the grounded support ing member 6 and to weld the conducting strap 24 to one of the trolley wire clamps 2 or bolt 4. However, it will be apparent that the invention may be adapted to trolley wire supports before they are mounted in position on the roof of a mine. In such case, the cylinder 23 would be cast integrally with the housing 6 or secured thereto in some other fashion during the fabrication of the insulating support. In like manner, the conducting strap 24 or stationary contact members 25 would be formed integrally with one of the trolley clamping supports 2.

In order to connect the conduit I3 to the trolley wire I, the handle II is manipulated to insert the grounding element 22 into the opening provided in the cylindrical element 23. The en gagement of the ground element 22 with the cylindrical element 23 provides a connection for the insulating material of the handle I! with ground. With the rod 22 positioned in the cylindrical element 23, the handle I I is then rotated to move the movable contact H from the position shown in Fig. 2 to a position between the contacts 25. There will then be provided direct electrical connection between the trolley wire I and the cable 13. It will be seen that the cylinder 23 provides a support for the handle 10 during its manipulation to make an electrical connection with the contacts 25.

By reason of the grounding connection provided by the rod 22, it will be seen that injury to the workman holding the handle H is effectively prevented. In the event that the conducting and; it. will thusnot benecessary to: interrupt; theconnection sothat a trolley may: pass by as is the case? with conventional: connectors.

The; preferred form; of the. trolley: wire: con.- nector illustrated inl Figs. 4' to. 9' inclusivediffers; from the: connector of. Figs. 1. and: 3 in:

the mounting of the contacts. which. are made between the trolley wire and. the; connector-- handle. The construction. of: Figs; 4; to 9 inelusive complies: with: the minesafety regula.- tions.

Referring to Figs. 5 ail-6.1.6.; the. trolley con.- nector. bracket Z-t. has a. boss 28. on the. back: thereof. adapted: to receive a; threaded fastening: membersuch. as. l which is: secured.- in the: roof; of a. mine. An. insulator: 3.0 is. secured within. thebracket 26 for the purpose of insulating and supporting: a trolley-wire l... The trolley wireis connectedto-a square or. rectangular shank. 3.2 which is embedded within thev insulator and arranged" tosposition wire clamps Z having a contact blade 34. thereon parallel to; the. trolley wire. This. arrangement insures that. when the bracket is properly positioned for supporting the trolley wire, the contact. blade. will: be parallel to. the trolley wire. A tubular grounding member 36 is: connected to a separablerbracket 3.8:; (liigzfi)- which; in. turn. is; connected: to' the. bracket. 236' by means of pins 40 and. bolt. 4.2... The bracket; 3.8 is. made in two parts, and. bolt:v 423 extends through. one

part: and is threaded into; thev other... The: pins.v

4.0- extendinto openings 44; in. the bracket in order; to position the tubular member at right: angles: to the trolley wire. Within thev tubularmember- 36' is; mounted a bronze ferrule 4.6; which is: split; andbent: inwardly: in orderto; make a, tight yieldingcontact with a pin. 4.8: (Figs; 5 andv 6) on. a. connector handle when. the. pin. is inserted-in the; ferrule. It is important to: maintain a tight, accurate. contact. between the: pin and. the ferrule. in; order to. properly close; the contact. members. which. connect the handles with the trolley wire.

In Fig. 4 is shown abracket having twov tubular members 59 and 52. which. areformed integral with the bracket 26. In this form. of bracket, contactblades- 54. areconnected with each of the trolley wireclamps so that a connector handlemay be mounted on. either side ofthe trolley wire.

The preferred form. of the. connector handle, is. illustrated particularly in Figs. 7,, 8, and 9.. This. handle consists of a. hollow insulation body 56, such as Micarta,. whichis connected to.an.insulation head '58. by means. of a threaded connection. 6.0. A forkedswit'ch contact member 62. is mounted' in the insulation head 58' within a cavity 64'. The cavity is open at one side and the bottom, so that when the contact member 62 is moved into contact. with the contact member 34 on. the trolley bracket. a portion of insulation 66 of the head will cover the switch. contacts so. that dirt. will not settle above the switch. contacts (see Fig. 5) that might. result. in a, short circuit of the electricalcircuit. The-switch member 62 is.-con-- nected by means of, a bar 68 with a metal, cylindrical connector 10 which receivesv one. end ofa fuse 12. The other end of the fuse ismounted'. in a. cylindrical. connector 14;. which in turn is connected. with an. insulated. cable 1:5, the cable being held. in. positionby means. of av screw 18.. The cable extendsthrough the. rear end of, thehandle, but. a. considerable portion oi the cable is mountedwithinthe insulated handle. At the rear. of the. connector 14 is. mounted a rubber gasket 80, and a rubber gasket 82 isv mounted in the front endof the. handle adjacent the threaded connector 60. Therefore when the handle is closed the gaskets are compressed to make the interior of the handle; moistureproof. The connecting pin- 48.- for the ground connection is mounted in the head 58 of the handle and is arranged to. move through the ferrule. 46 on the bracket when. the handle is connected with the trolley line bracket.

With; thearrangement described above, the contact blades. for the trolley 1ine will be arranged parallel to thetrolley line, and the tubular members for positioning the contact handlearranged to position the contact member in the handle, so that when the handle is rotated in the: tubular member, the fork switch member. 62 will clampv down: over the knife blade 34 tomake a good electrical connection. From Fig. 5 also building up on the blade to make a grounding contact and thus short circuit the electrical circuit of the trolley wire.

The preferred form. of the invention having been thus described. what is claimed as new is:

1. An electrical. connector for making a. dctachable connection to. a trolley wire or the like comprising a handle formed of insulating ma.- terial, a stationary contact connected with said wire, a movable contact mounted on said. handle for movement thereby into engagement withsaid stationary contact, a member at ground potential and having a cylindrical opening therein, and a rod. projecting outwardly from. said handle, sai rod being receivable in said opening to place said handleeatground potential. said member forming.

' tachable connection. to a trolley wire or the like hayingqsupporting, structure including a conducting. member at ground potential, a conducting member; in. contact with said trolley Wire, and electrical insulation between said members, the combination comprising a handle formed of insulating material, a grounding element having an opening therein connected to arm. n. conducting member. a rodembedded in the insulation of said handle and receivable in said opening to place said handle. at. ground potential, and a contact carriedby said handle, grounding element providing a pivot support about which said handle may be rotated to en gage; said contact. with said conducting member in contactwithsaid. trolley wire.

3. In. apparatus for making a detachable electrical connection to av conductor having a support, the; combinationcomprising a. mounting part having. a circular opening therein secured. to said support. a; stationary contact part on. the support and.electricallyv connected with the conductor, a handle formed of. a body of insulating material and. having. a mounting rod projecting therefrom; said. rod. being. receivable in saidopen- 6 ing to mount said handle on said support for rotational movement in opposite directions re1ative thereto, and a contact element mounted on said handle for engagement with said stationary contact part to complete an electrical connection, manual. rotation of said handle in opposite direc tions with rod in said opening being effective to move said contact element into and out of engagement with said stationary contact part to make and break said electrical connection.

4. In apparatus for making a detachable elec trical connection to a trolley wire, the combination comprising an insulat r support for the trolley wire including a mounting part at ground potential, a grounding element having a circular opening therein and an electrical connection with said mounting part, and a stationary contact structure having an electrical connection with the trolley wire, said stationary contact structure comprising a pair of spaced parallel contact elements respectiv the axis of said opening, a handle formed of in suiating material and having a mounting rod projecting t: erefrom, said rod being receivable in said opening to mount said handle on said support for rotational movement in opposite directions relative thereto, and a movable contact structure mounted on said handle comprising a knifc-like contact element in a plane perpendicular to the axis of said rod, manual rotation of said handle in opposite directions with said rod in said opening being effective to move said knifelike contact element to and from a position between said spaced parallel contact elements in which it completes an electrical connection between. said stationary and movable contact structures.

5. In apparatus for making a detachable elec trical. connection to a trolley wire, the combination comprising an. insulator support for the trolley wire including a mounting member at ground potential, a first grounding element having an electrical connection with said mounting part, and stationary contact structure having an electrical connection with the trolley wire, a handle iormed of insulating material and having a second grounding element projecting therefrom for engagement with said first grounding element to place said handle at ground potential, and a movable contact structure mounted on said handle for movement thereby into engagement with said stationary contact structure, and means ineluding said first and second grounding elements forming a rotatable mount for said handle on said insulator support about which it may be rotated to move said stationary and movable contact structures into and out of engagement with each other.

6. In apparatus for making a detachable elec-- trical connection to a trolley wire, the combination comprising an insulator support for the trolley wire including a mounting member at ground potential, a grinding element having an electrical connection with said mounting part, a stationary cont-act structure having electrical connec' tion with the trolley wire, a movable contact structure on the insulator support having an electrical conductor connected therewith, and means including said grounding element forming a rotatable mount for the movable contact structure about which the movable contact structure may be rotated. into and out of engagement with said stationary contact structure.

7. A separable connector of the class described comprising a support member and a connector in planes perpendicular to member, said members having interfitting metal pin and sleeve elements for slidably interengaging each other and forming a separable union between the two members, the support member including a metal trolley wire bracket connected with a trolley wire, a grinding insulator for the bracket, and an anchor part carrying the irrsulator, one of said interfitting elements first mentioned being on the anchor part of the supportiru member, the connector member comprising an insulating body on which the other of said interfitting elements is mounted, a contact on the insulating body of the connector member, a contact on the supporting member electrically connected with the trolley, the said contacts of the respective members being offset with respect to the interfitting elements of the respective members to require the engagement of the interfitting elements before the contacts can be engaged and remain interfitted until after the contacts have been disengaged, the relative sliding movement of said elements serving to guide the contacts into and out of engagement, and means for connecting a cable with the contact of the connector member.

8. The trolley wire connector defined in claim 7 in which the sleeve element of the connector member is substantially at right angles with the trolley wire and the contacts on the supporting and connector members are arranged to make sliding contacts with each other in a plane at right angles to the axis of the sleeve axis.

9. An electrical connecting device for a power takeoff from a trolley line comprising a grounded trolley wire supporting bracket, an insulator car-- ried by said bracket to which the wire is connected, a thin blade contact connected with the line and insulator, said blade being supported in a vertical position, a tubular grounded contact member mounted on the bracket, a separable connector comprising an insulating handle having a grounding pin arranged to slidingly enter the tubular member on the bracket, a contact in the handle arranged to make electrical contact with the trolley contact when the handle is rotated about the tubular member, said tubular contact member and the grounding pin being arranged so that the pin extends a substantial distance into the tubular member before the contact for the trolley wire and the handle connector may be brought into contact with one another, and a cable connected with the contact in the handle.

10. The connecting device defined in claim 9 in which the contact in the handle consists of a pair of spaced contact jaws so positioned in the handle that the handle will cover the contacts when the contacts are closed.

11. The connecting device defined in claim 9 in which the contact blade connected with the trolley line is positioned parallel with the trolley line and the grounding tube is mounted at right angles to the trolley line to position the away from the trolley line.

12. The connecting device defined in. claim 9 in which a rectangular supporting shank is en-- bedded in the trolley insulator and connected with the trolley line to position the trolley line contact blade parallel to the line.

13. The connecting device defined in claim 9 in which. the tubular ground contact is remov ably attached to the bracket and arranged to hold the tubular member at right angles to the trolley line.

14. The connecting device defined in claim 9 in which tubular grounding contact members are mounted one extending out at each side of the bracket to permit electrical connection at either side of the trolley.

15. The connecting device defined in claim 9 in which a yieldable clamping ferrule is positioned within the tubular member to align the handle in position for making contact connections.

16. The connecting device defined in claim 9 in which the handle is a hollow body of insulation material having a fuse and cable connections therein having a threaded connection with a closed insulation head, an opening at the rear of the handle to receive an insulated cable and gaskets mounted within the handle at the front 10 and rear thereof to seal the interior of the handle against moisture entrance.

JOHN L. MCGLOTHLEN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 913,419 Moran Feb, 23, 1909 1,594,925 Chandler Aug. 3, 1926 2,246,193 Smith, Jr. June 17, 1941 2,472,000 Bowen May 31, 1949 2,532,454 Kane Dec. 5, 1950 FOREIGN PATENTS Number Country Date 367,353 Germany Jan. 20, 1923