How do they change tracks to go on other streets?rambo1..
By using switches. They usually only had one moving rail, though.
The single-point switch and girder rail were specifically designed to be laid in pavement. The motorman would dismount and throw the switch with something like a crowbar. Some were locked with a little block of steel, others were left free so another car could come through a trailing point move without derailing. There were also single-point spring switches, used where the track was single between stops and double at stops.
The ultimate expression of street railway specialwork was the, "Grand junction." Double track crossing, right hand running, with connecting curves for every possible route on the cross street. Sixteen turnouts (or eight lap turnouts) eight curves, sometimes curved rail running right through an otherwise normal (for girder rail) frog. Putting one at the busy crossing next to city hall and the county courthouse meant that the company had reached the big time.
Of course, the authorities could (and often did) screw that up by creating one way streets.
Chuck
The movable tongue mentioned in earlier responses was different from the RR type in that instead of bending the rail, it pivoted at a point about two feet or so back from the point. The other rail had a fixed frog-like arrangement that supported the flange and let it take either path.
Here is a picture that shows the switch rod that tomikawaTT mentioned. It's from "The Streetcars Of New Orleans" by Louis C. Hennick and E Harper Charlton. It is hanging next to the middle window at the motorman's right side.
https://www.flickr.com/photos/paulofcov/15573946851/in/set-72157626021256880
The practice in early days was for the motorman to lean out the front window to operate the switch. In later years, a current sensing method was used. Here is a discussion of it. Go to the "Pointswitching" section.
http://en.wikipedia.org/wiki/Tram_controls
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"A stranger's just a friend you ain't met yet." --- Dave Gardner
rambo1are there sensors in the tracks?
The "sensors" are usually current detectors wired in series to the overhead wire, which is arranged in insulated sections. They operate a signal system, if the trolley line has one, and could be wired back to the dispatcher's office to provide approximate location of powered cars.
As far as sensors for vehicles and people on the tracks, the motorman had to depend on the Mark I mod zero eyeball.
Living in Toronto as I do and having nollij of the streetcars as I ride them every day, there is a remote control box up on a telephone pole near the switch itself. The driver pushes a button, and usually the points will move. Often it doesn't and the driver has to use a switch iron to move the points. Often when there is a diversion, there will be a TTC staffer sitting on a folding chair with his own iron and he will move the points as a specific car approaches. This happens a lot as there are car crashes, construction and track maintentance and so forth that requires a man to be stationed at an intersection, which are mostly of the "grand union" type.
You can be standing at a stop and the car that is approaching, say a Spadina car the is turning around at King Street and the point (only the one blade on the inboard side) will move with a loud "schwack" noise. Like I said, it doesn't always work due to snow and ice or for whatever reason and then the driver has to get out and use the iron.
Sometimes the pole comes off the wire and there is a loud BZZZAP! and you look out the rear window and the pole is bobbing around and the car stops dead, usually in the middle of an intersection such as near where I live at the junction of King st, Queen st, and Roncesvalles avenue near the car yard. Anyway, the driver gets out and puts the pole back onto the wire and on we go. Life in Toronna!
Did not see mentioned the take up spool. On both single pole and double trolley poles is a oversized bell shaped housing that the trolley pole rope is attached to. Whenever the pole jumps off the trolley wire the sudden extension of the rope releases a spring mechanism that takes up the rope pulling a pole away from the over head wire(s). TT bus or car operator then goes to rear of vehicle, winds up the take up spool by pulling on the rope several times then operator can then slowly allow trolley pole to re engage wire. If for any reason rope slips then take up spool the pulls pole down and operator can try again. Also this appplies whenever changing ends on double ended cars. Protects pole from snagging overhead power wire(s).
One time observed a trackless trolley ( 2 poles ) that had a rope break as pole jumped wire at a wire switch.. Quite a spectacular electric arc show. Then uderstood reason for take up spool.
This speaks to the present standard of new facilities using PANs and some older operators adding same.
In the "classic" streetcar era, many lines used contactors in the overhead to control switch machines, swithc position depending on whether the car was drawing power or not when passing the contactor. The device used to pull down the trolley rope is either a "catcher", if it simply stops a fast rising pole, or a "retriever" if it will pull a loose pole down.
Rcdrye: Have never observed a catcher but makes sense. The reteriver is the one that operator has to wind up after a loose pole ?
In Toronto, there is a rope on a reel at the back of the car. When the pole comes off the wire, it just unwinds and the pole will bang around the supporting wires often sending out sparks. The driver pulls the rope down to reset the pole. The reel is shaped like a fire bell on the wall of a building.
It sounds like Toronto uses catchers. The catcher has to be adjusted soft enough so that changes in wire height won't trigger it, which means that a pole will rise a couple of feet when it dewires.
Nearly all PCC's used catchers, PE's being the only exception.
I assume their CLV and ALV Toronto replacements were similar in that respect.
The catcher works on a principle like a roller blind, but I don't understand how they work, either.
Toronto is supposed to have sensors operated by a button in the car. They don't seem to be reliable and a lot are out of use.
The old system had a contact on the trolley shoe, a strip of metal by the wire and a button on the dash. If the car went through the metal strip the switch point would throw straight. If the NA button were pushed, the point would throw curved. (NA= Necessity Action) Some were set so that going through the contact strip would set the point straight; to go curved the operator had to get out with the switch iron. (SR=Self Restoring) This system was abandoned when the articulated cars came and the poles were at two different distances from the front of the car.
After a rainstorm. there would be a great splash of water when the point changed over.
--David
Newer streetcar lines use embedded radio receivers to operate switches. The switches will only receive the signal from an approaching streetcar once it is within the limited range of the receiver. Antennae for the switches are mounted under the floor of the streetcar and the operator presses a button in the cab to transmit the signal.
The large crossings that street railways used to make turns to every quadrant are called grand unions.
Jerusalem Light Rail uses a form of CTC to control all dispatch signals and all switches, with the position light signals (mineatures of classic PRR-N&W signals) showing the switch position. And all switches including the one street-imbedded slip switch, have pairs of movable points, not like the single-point classic streetcar switches. The position light signals are independent of the traffic road-crossing white-bar singals, coordinated with the traffic lights, with of ocurse a horizonatal bar indicated stop, vertical go, and dot about to change.
daveklepperHighg speed interurbans, such as the North Shore, usedd retrievers of necessity. This made raising and lowering the poles, using the rope between cars as well as at the end of the train, a paarticularly delecate operation, between howard St. and Demster, in rain and snow.
The raising of the trolley poles between Howard St. and Dempster always amazed me, as it was done on the run as the train was picking up speed. There was a long stretch of wire without cross-wire supports which gave a little grace if the pole missed, but it usually didn't miss. At the time I rode it most I was having to raise and lower poles on the west end of the Lake St. Elevated, and standing stock still it wasn't a simple task.
CTA had to make similar adjustments to the overhead in 1964 when the Skokie Swift began service. Pan trolleys were used to allow one-man crews without a stop to change from third rail to overheard.
rcdryeIn the "classic" streetcar era, many lines used contactors in the overhead to control switch machines, swithc position depending on whether the car was drawing power or not when passing the contactor.
I've seen this in action in the "modern" era on SEPTA...
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
Don't you mean you used to see it? I don't think SEPTA uses the overhead wire to control track switches anymore, I thought they had changed over to some mechanism buried in the asphalt, and did so sometime in the 1980's.
Patrick Boylan
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Trolley poles will remain in use on San Francisco's F line. And to and from the carhouse, the track is shared with the Breda pan-equipped Light Rail cars. See www.streetcar.org
Both San Jose and Sacramento have mods to allow trolley pole usage for heritage cars. Overhead has hoops around the frogs to allow pans to pass.
San Francisco's "J" line is used by "F" line cars to get to the San Jose Avenue maintenance area, on the site of a one-time Market St. Ry. barn.
Boston's "T" Green line still has a fair amount of pole-equipped work equipment.
gardendance Don't you mean you used to see it? I don't think SEPTA uses the overhead wire to control track switches anymore, I thought they had changed over to some mechanism buried in the asphalt, and did so sometime in the 1980's.
I believe I saw it at the exit to the subway surface tunnel in the mid 1990s....
Both exits from the subway surface tunnel are places where I'd have expected SEPTA to have changed over to the newer track switch control method sooner than other spots. At the 36th St portal oner route diverges from the other 4, so it has more traffic than the 40th St portal, which had gotten reconfigured from a 2 track T arrangement to a circle with 3 entrances and exits. I'd be flabbergasted if anyone has proof that they reconfigured it with the old fashioned overhead wire power on-open power off-close switch controls and subsequently changed it to the newer system. I think SEPTA calls it Vtag, but I have no idea what Vtag means.
The operating historic cars, PCCs and Milan Peter-Witts, have generally been moved from Geneva Division to the new Third Street complex, with the display historic cars, MUNI 1, Blackpool boats, etc., kept across the street from the old MSR building in a new display heritage car facility covering the old outdoor storage tracks. The old MSR building is no longer a car house but serves community purposes. See www.streetcars.org So even the new Third Street line is equipped for trolleypole operation as well as pantograph. In fact, I think the only part of the MUNI network that cannot accomodate pole-equiped cars in the subway itself.
what about streetcars which used ploughs, rather than overhead (e.g. Capitol Transit within Washington D.C. limits)? ---- my first exposure to anything but the trackless-trolleys in Seattle; & do they (t-ts) even count as "streetcars," being essentially a rubber-tired bus powered from overhead?
saxhornwhat about streetcars which used ploughs, rather than overhead (e.g. Capitol Transit within Washington D.C. limits)?
We've discussed them here -- look in 'search conversations' using the term "conduit".
... do they [trackless trolleys] even count as "streetcars," being essentially a rubber-tired bus powered from overhead?
I think this is a matter of taste. Personally I find TTs interesting, but not in the same way streetcars are... with some exceptions. The trolleybus operation through the tunnel under Harvard Square in the mid-70s was fascinating...
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