Daimler Twenty-Two



Their new Daimler 22 horsepower full-size luxury car was first displayed by Daimler in April 1902 at The Automobile Club’s Exhibition in London's Agricultural Hall. Daimler had elected to drop their multiple old low powered designs and restrict themselves to this 22 horsepower and a pair of 9 or 12 horsepower cars to the same design as the 22 but more lightly constructed. The King’s not quite finished new Daimler 22 was reported to be the chief attraction of the show.

The 22 horsepower cars were geared to run at about 40 to 50 miles per hour when the engine was running at normal speed.

The following January 1903 Daimler, having earlier dropped the 9 hp, replaced their 12 with a 14-horsepower car making a range of just two vehicles.

In January 1904 Daimler introduced a wholly new range of four cars including a 3.8-litre 18/22.

New range
The 4½-litre 22, and its 3.4-litre stablemate the 12, were developed and their construction organised by Percy Martin then works manager. The twin-cylinder 9 hp car was soon dropped. Although they were first displayed in April deliveries did not begin until July and a steady production stream did not eventuate until November 1902. These new models were the product of the board's decision to end production of old type cars and restrict the range to two or three models with standardised interchangeable components. This new range was between 25 and 30 per cent lighter than their preceding equivalents and had much improved speed and hill-climbing power. All the wheels were now the same size. The redesigned steering helped to make them easier to drive. The lowered chassis frame increased the cars' stability and made entry easier. The more rigid chassis frame improved the alignment of the transmission system. Finally this new model cost 17 per cent less to manufacture than its predecessor.

Bodies
Standard bodies were built in Daimler's own body department which would also provide bespoke bodies on different wheelbases to special order. Chassis were made available to customers' own coachbuilders. The same body was used on the 22 hp as on the 9 and 12 hp chassis.

Engine
The 4-cylinder, 4½-litre side-valve engine is a pair of cast iron twin-cylinder blocks bolted to an aluminium crankcase cast in upper and lower halves.

It develops 22 hp at 720 rpm at which speed in top gear the car should be running at between 40 and 50 mph.

The engine's governor regulates by suspending the action of the exhaust valves consecutively. There are also throttle valves under the control of the driver.

The four forward speeds are selected by one lever, reverse by a small lever on the footboard. The crankshaft has three main bearings. Two double rings are fitted to the pistons. The skirt of each piston is reduced slightly in diameter to form an oil retaining space. The steel connecting rods are drop forgings. Gudgeon pin bearings are bushed with steel, the gun-metal big end bearings are lined with white metal as with all other bearings throughout the engine. The camshaft is driven from the crankshaft by spur wheel. The camshaft bearings are part of the crankcase covered by an upper half that is a separate casting and provides a guide for the pushrods. The camshaft’s forward end carries the centrifugal governor. A half-inch pitch roller chain links the drive to the commutator mounted on the car’s dashboard. The camshaft is lubricated by splash from the crankshaft. Throttle valves are worked by the driver.

Petrol is supplied by gravity from the tank at the rear of the car but once the car is under way exhaust gases maintain a pressure within this tank. A lubricating oil tank is pressurised the same way. The petrol tank is in two compartments separated by a partial partition. Both sections are filled when the tank is filled above that partition but when the larger tank is empty the second tank provides a fresh supply and a timely warning to the driver.
 * Dashboard
 * Fuel

An exhaust box is mounted on the near (left) side between the countershaft and the back axle. After passing through this box the gases are led across the back of the car in a pipe with a perforated underside to minimise the dust stirred up. The starting handle passes through a water tank at the front of the car. The radiator is fixed immediately above this tank. Its sides are of ribbed aluminium castings connected by finned tubes run horizontally across the front of the car. The ribbed aluminium castings inspired Daimler's flutes. The water circulating centrifugal pump is driven by a friction wheel pressing against the flywheel. Two pressure lubricators feed the pump's bearings. The design ensures natural circulation would continue if the pump were out of order. There is a sheet metal casing beneath the engine as a dust-shield.
 * Cooling

Chassis
All four wheels were 36 inches diameter artillery style with steel axle boxes and thickened spokes to carry the chain drive sprocket wheels. Suspension was by "grasshopper" (semi-elliptical) springs 36" behind and 31" in front. Chassis weight under 22 cwt. Wheelbase 7’ 6" and the track or "gauge" 4’ 7½" The wheelbase of the King’s car had been increased to 9’ 0".

The wooden main frame is strengthened by tapering steel fishplates along the inner faces of the longitudinal members. One of the transverse-members supports the change speed lever. From these transverse members an underframe is suspended and it supports the engine at a level below the main frame.

The clutch and flywheel are mounted on the back of the engine block This part of the clutch is of aluminium and carries a friction surface of leather To make for a more gradual engagement a steel spring is set between the leather and the metal face. It is formed into a ring with projecting tongues which ac t as springs. The large spiral spring to hold the clutch in engagement is stationary. It acts on the fork imparting a sliding motion to the propellor shaft. A ball bearing takes the thrust between fork and the shaft. A long propellor shaft runs from the clutch to the gearbox's first motion shaft. This propellor shaft carries a flexible coupling and is splined to allow longitudinal movement together with the clutch. The gearbox is mounted between the back axle and the sprocket shaft for the chain drive.

When the handbrake is applied the (otherwise fixed) end of the spring is moved forward by a cam which releases the clutch and the car may stop without affecting the engine. Application of the footbrake has the same effect. This arrangement was deleted from the next model now the driver has control of the throttles and engine braking may be used to reduce the load on the brakes.

The transverse casing of the countershaft the differential and the gearbox is of aluminium alloy and it covers the entire transmission gear. The change-speed lever is mounted on this casing. The transmission has eight ring-lubricator type bearings fed by pipes from feeders with gauge glasses visible from beneath the car. Power is transmitted from the transverse countershaft to each rear wheel by 1½ inch pitch roller chains. When necessary the complete gearbox may be removed downwards.

Four forward speeds separate lever for reverse
 * Gearbox

The foot pedal operates by rod a transmission brake mounted on the rear end of the gearbox's second motion shaft. It is described as a powerful double-acting band brake. The brake's drum is surrounded by a water jacket. The hand lever operated side brakes (on the rear wheels) are also double-acting band brakes. These drums are fixed to the rear wheels. The operating lever is inside the car by the right hand of the driver. The system of rods and levers incorporates an equalising arrangement.
 * Brakes

There are two semi-elliptic springs on each axle. The back axle is located by a pair of distance rods fixed to the main frame by the same brackets as the final drive and gearbox. Used to tension the chains they are free to swing about the same centre but place no strain on the countershaft's bearings.
 * Suspension

Steering is operated through a worm gear fixed to the steering column. It engages with teeth on a projecting arm which operates a rod in the usual manner. Ball sockets are fitted to the various knuckle joints.
 * Steering

Royal cars
The body of the King’s car was arranged to carry two on the box at the front and six people behind in the tonneau. The two rearmost seats have rounded backs. Curved glass panels reach up to the canopy and provide protection from dust. A glass panel above the door gives access to the rear of the carriage. Side curtains are provided. The car is upholstered in blue Morocco leather and the body is painted in crimson lake lined with red. In January 1903 it was announced the King had ordered a second Daimler 22. A week later again the King ordered a third 22 for the use of the Prince of Wales.

Further development
Bodies are now hinged at the rear and may be tipped up for inspection of the mechanicals. Ignition is electric though supplementary tube ignition may be supplied to special order. The wheelbase has been lengthened and the bottom half of the crankcase is now detachable. A driver may now use the braking effect of engine compression because the handbrake no longer automatically disengages the clutch. The countershaft sprockets are now easier to change. At the beginning of 1904 a new range of four Daimlers was announced. A 2-cylinder 1.8-litre 7 horsepower (12 tax horsepower) car, a 4-cylinder 3.3-litre (20 tax horsepower) 16/20, a 4-cylinder 3.8-litre (22.4 tax horsepower) 18/22 and a 4-cylinder 5.7-litre (30 tax horsepower) 28/36.
 * Improvements for 1903
 * 1904 replacement models