The 10th International Portafold & Ansfold Gathering (i.e. 2018)

Following the huge success of the 9th International Gathering we'll be at Retrofestival again. It's a massive show now and is popular with everyone.

It's held at the Newbury Showground, Priors Court, Hermitage, Thatcham, West Berkshire, RG18 9QZ; on the weekend of the 10th, 11th & 12th of August 2018.

Don't book with the organisers, contact me to get your pitch saved.

Brakaway linkage mod

Anything you've created that didn't come out of the factory.
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txfsealord
Posts: 177
Joined: Sat, 05 May 2007, 9:24 pm
Location: Pulborough, West Sussex

Brakaway linkage mod

Post by txfsealord » Fri, 01 Jun 2007, 6:38 pm

Hi all, it occurred to me today that the emergency brake cable, which pulls the brake on if the trailer comes off the tow hitch, isn't any good on the old-fashioned hitch on our Ansfold. Because the ratchet pawl is folded back during normal running, once the cable is snapped by the trailer's brakes coming on, without the ratchet they just go off again. On a modern hitch, the handbrake is held in the 'on' position by a large tension spring. Once the cable pulls the spring over-centre, the brakes come on & stay on.

So, QUESTION: Is there a doofah on the market to do this for the original type of hitch? Or should I settle down & work out a mod to add to the existing arrangements?

Steve
Last edited by txfsealord on Sat, 30 May 2009, 7:18 pm, edited 1 time in total.

txfsealord
Posts: 177
Joined: Sat, 05 May 2007, 9:24 pm
Location: Pulborough, West Sussex

Brakaway linkage mod

Post by txfsealord » Wed, 25 Jul 2007, 5:29 pm

Just in case anyone's interested.........rather than try & buy anything, I made my own. Whenever I attempt to get chassis hardware for this trailer, I seem to draw a blank! Or is it me.......? Anyway, I cut the top off the handbrake lever about 3/8" above the large nut on the back of the hitch plunger. This 'rocker arm' lower bit works the overrun brakes exactly as it always did. I shaped a length of flat strip into a horseshoe, big enough to allow the hitch-nut to fit through it. It runs on the same pivot point as the rocker, outside the clevis on a longer bolt, and extends down to the level of the brake cable. The rest of the original lever, complete with pawl, is welded to the top of the horseshoe. A tappet-plate inside the horseshoe, just clear of the large hitch-nut, strikes the top of the rocker to put the handbrake on & the safety cable pulls on the bottom end if the 'van separates from the car. The ratchet is permanently 'on', aided by a tension spring. Another spring keeps the handbrake in the 'off' position against vibration.

I once saw a similar arrangement on a 1950 Eccles chassis........no doubt others have used it too. I hope I never have to find out if it works or not!



Pictures below:
AnsfoldBrakawayMechanism1.jpg
Brake lever from above, viewed from the offside. The cut-off top of the original lever can just be seen within the "horse-collar" shaped arch I've added to the hand lever, after cutting the lower part from it. The large spring ensures the lever doesn't vibrate up when running. The small spring keeps the pawl engaged with ratchet teeth on top of the hitch casting.

AnsfoldBrakawayMechanism2.jpg
View from above, nearside. The hand lever is raised, applying brakes through striker plate (above the large nut) pushing on the top of the main lever directly above the hitch pushrod. I've relieved the "horse-collar" on this side to clear the jockey when on full lift, although if the brakes are correctly maintained, there's bags of room here. (NB I put my jockey within the A frame to permit more angle between car & caravan without causing expensive bumper-damage).

AnsfoldBrakawayMechanism3.jpg
Viewed from nearside. Here, the hitch is compressed to apply the brakes. The hand lever is down.

AnsfoldBrakawayMechanism4.jpg
From nearside, below chassis. I drilled 3 more clevis-pin holes above the original to permit convenient adjustment of leverage, or 'braking effort'. Ansfolds were intended to be towed by cars with disc brakes, it seems. Mine has drums, & needs more help from the trailer-brakes than given by the maker's setting.

I've also added a small brace beneath the front of the chassis' clevis, to prevent the clevis twisting when the brakes are applied. This sharpens the brake actuation. The basic design of these brakes is excellent; a little detail attention has given me the best trailer anchors I've ever known.

AnsfoldBrakawayMechanism5.jpg
From beneath tow-socket, looking rearwards. The white link with chain hanging down is the hand-lever extension from the offside leg of the "horse-collar".

AnsfoldBrakawayMechanism10.jpg
AnsfoldBrakawayMechanism9.jpg
AnsfoldBrakawayMechanism8.jpg
AnsfoldBrakawayMechanism7.jpg
AnsfoldBrakawayMechanism6.jpg

Steve

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