A NEW LOW-LEVEL CABLE CARRIER.
Page 14
If you've noticed an error in this article please click here to report it so we can fix it.
A Six-wheeler with Detachable and Interchangeable Trailer Units, One of Which Has a Platform Only 30 ins. Above Road Level.•
MO MEET the requirements of Robert Wynn and Sons, Ltd., haulage contractors, Newport, Monmouthahire, li'odens, Ltd., have constructed a six-wheeler for the purpose of carrying drums of telegraph cable, the vehicle having been delivered to the owners during the past few days.
• The vehicle is intended for more than one purpose as, besides being equipped with a cable-carrying trailer portion, it also has a standard six-wheeler trailer complete with rear axle and brakes, its platform being at normal level, so that it is possible, whenever • necessary, to change over from cable-carrying to a. vehicle with a standard platform level. All that is necessary in order to arrange for the conversion is to remove four castle nuts which hold the turntable. dish to the Platform and then to support the forward end of the trailer portion on jacks, as will be described later, the tractor then drawing clear ready to pick up the alternative body.
To describe the cablecarrying trailer, this is constructed of heavy-section channel iron 7 ins, deep by 3 ins, wide, well braced by cross-channels and steel plates. The front of the frame is constructed to carry the usual turntable dish, to the rear of which it suddenly dips down to a very low platform, the height from the ground to the top of the platform boards being 30 ins. This is considered to be the lowest six-wheeler at present on the road. .Having such small wheels that they come entirely below the platfotm, it gives the added advan The rear end of the low-level cable-carrier, trailer, showing the wide tyred wheels and the springing.
tage that the platform may be extended to the full width of 7 ft. 4 ins. Obviously this gives a very large platform area.
The rear axle is square in section and is equipped with two llildershing springs, in addition to which provision is made in the frame to accommodate a check spring, Which is supported against the frame and slides on the top of the square axle, coming into action as the full load is imposed upon the platform. This method of spring support has been tested with# load of 12 tons on the rear axle and is said to have proved extremely, effective.
The axle carries two cast-steel wheels fitted with solid rubber tyres, the fitting size of which is 181 ins., whilst the width of the tread is 12 ins., the outside diameter of the wheels being 25 ins. These wheels are equipped with brake drums 16 ins. in diameter and 4 ins.
CIO
wide, into which are fitted brake shoes which may be expanded by means of a cam operated from the driver's seat. The wheels are thounted on very heavy roller bearings and are probably the smallest wheels of the kind to be used on this class of work, the tyres having had to be specially made.
Mounted at the front end of the trailer and immediately over the turntable dish is a winch which has a purchase gear for hauling cable drums on to the platform and for lowering therefrom, a ramp at the rear being used also as a tailboard and being wound up or lowered by means of the winch, two mild-steel stays beimg provided to keep the tailboard rigid when travelling.
To return to the winch, this has machine-cut • gearwheels with a 20-degree stub tooth, being designed to handle loads of 5 tons. It is fittedwith a ratchet wheel and pawl and has a powerful hand brake. The winding drum carries over 100 ft. of
steel-wire rope and is arranged to be operated by hand. Anchorage rings are fixed at intervals along the platform for the purpose of securing the load when necessary.
At the forward end of the frame are hinged two supporting jacks which are lowered and extended in order to support the weight of the front of the trailer, the rear wheels being scotched during the operation of detaching and attaching. When the front of the trailer has been raised on the jacks, after removal of the 1i-in. nuts already referred•to, the tractor can be driven from
under the 'frame and backed under the alternative frame with the high-level platform which, of course, should be already jacked up and ready for coupling up by means of the four nuts, the jackS then being contracted and fastened up to the frame. All that is necessary in order to crimplete the conversion is the coupling up of the brake cable. If done systematically, such a change-over can be effected in about 20 minutes.
The usefulness of these trailer vehieles is considerably -increased by an extension of the rear sub-frame on the high platform which carries the rear springs.