PH Origins: The electric starter
Cadillac's renowned for popularising the electric starter in 1912 - but the concept is decades older
In late 1907, American automotive pioneer Byron Carter reputedly came across an innocuous scene. A lady, driving across the Belle Isle bridge in Detroit, had stalled her Cadillac. Getting it restarted was no mean feat, as it involved setting the timing correctly and hand-cranking the engine.
Carter was no stranger to the process, having developed and patented several automotive technologies. He had also founded two automotive companies, the second of which - called 'Cartercar' - would be bought out by General Motors in 1909.
Naturally, he stopped to help the stranded motorist. Carter, who was 44 at the time, promptly set about cranking the engine over in order to get the car and its driver on its way. Unfortunately, the owner didn't retard the ignition; consequently, a cylinder fired before the piston had reached the top of its stroke, viciously driving it back down the bore and causing the engine to kick back.
The crank, suddenly reversed and spun with tremendous energy, broke Carter's arm and smashed his jaw. By chance, a pair of Cadillac engineers arrived on the scene and rushed Carter to the hospital.
Alas, while recovering from his injuries, Carter would contract pneumonia. Little was known about it and no real treatment existed then and, sadly, Carter would ultimately succumb to the illness on April 6, 1908 - leaving behind a wife and three children.
The engineers, Ernest Sweet and Bill Foltz, reported what had happened to Henry Leland (pictured, with the substantial goatee) - the man who had founded Cadillac in 1902 and also a close friend of Carter. According to a later biography, Leland exclaimed: 'I'm sorry I ever built an automobile. Those vicious cranks; I won't have Cadillacs hurting people that way.'
Leland, determined to not have such an event repeat itself, committed Cadillac's engineers to finding a way to abolish hand-cranking an engine. Risk aside, it was also becoming harder; engines were getting bigger and more complex, so they had more weight and friction that had to be overcome, and compression ratios were climbing. As a result, drivers who weren't frequently popping to the gym would often struggle with hand-cranking.
The development of such a system proved problematic, though, and Cadillac couldn't come up with a reliable starter motor assembly that was compact enough while providing enough torque to turn over the engine. Some of the starters tested were almost as big as the engines themselves.
Fortunately, a solution soon presented itself. At the time, Cadillac was being supplied with high-energy ignition systems by a newly founded business called the Dayton Engineering Laboratories Company - Delco. The company's co-founder, engineer and inventor Charles Kettering, learned of Cadillac's issues and suggested to Leland that he might be able to develop a practical solution.
Kettering, as luck would have it, had experience with high-torque electric motors. Prior to Delco, he had worked for the National Cash Register Company in Ohio. The company's products were top of the line but lacking in innovation; the tills, for example, required laborious manual cranking to operate. Kettering, who graduated with a degree in electrical engineering in 1904, had been employed by NCR to modernise the company's line-up - bringing in new ideas and concepts that could allow NCR to make more money.
His flagship innovation, while at NCR, was the development of a suitable motor to allow for automatic operation of the cash register's mechanisms. He had realised that a large, bulky and powerful motor that could run continuously was unnecessary - and that the system only needed a compact electric motor that could deliver a short burst of torque. By 1906 he had come up with a series of advances that permitted the production of a powerful electric motor small enough to fit into a cash register; before long, electric NCR registers were proving a hit with numerous shops and businesses.
Kettering (pictured at his workbench, with the starter, and in portrait wearing glasses) then moved on from NCR and collaborated with his associates to form Delco, in an effort to capitalise on the rapidly expanding and modernising automotive marketplace.
Although the scale of the problem was somewhat different, Kettering had presumably drawn the same conclusion with regards to electrically starting a car - in that a small electric motor could potentially be used, provided it could output enough torque, as all it would have to do would be to crank the engine briefly to get it to fire.
Kettering had a key prior innovation to draw upon, too. In 1901, an inventor from New York - Clyde Coleman - had created a combined starter-generator assembly for use in early automobiles. It would be coupled to the engine and generate electricity, which would be stored in a battery; if the engine was stopped, power from the battery could be used to turn the engine over to start the car. Coleman is stated to have further developed this concept but, in any case, it seemingly proved impractical and went no further.
Elements of Coleman's designs proved useful to Kettering, so Delco licensed one of Coleman's later patents and Kettering ploughed his expertise into developing a practical solution - crucially, making good use of his earlier experience with compact high-torque motors. Like Coleman, he focused on making an integrated system that would combine both stating and generating functions. Crucially, Kettering came up with a 6-24 volt system - the motor, when energised to start the car, would be supplied with a hefty 24 volts to boost its torque output. When it was being turned by the engine, however, its output would be regulated to six volts to charge the battery.
A series of constant refinements eventually led to the production of a starter motor that was small enough to be fitted to an engine and, in February 1911, one had been installed in a Cadillac. Leland tested it, liked it and promptly ordered 12,000 Delco starters. By 1912, they were being offered in Cadillac cars - and they soon began spreading through the myriad brands owned by parent company General Motors. According to Kettering, 'Inside of two years it was pretty hard to find someone who wasn't thoroughly sold on the idea. Cars that were not equipped with the new device simply faded out of the picture.'
Companies such as Bosch were not far behind and it would unveil its own electric starter motor in March 1914; by 1927, it had sold 11,000. By 1933, as the technology began to spread further afield and costs began to fall, it had sold almost 550,000 starters.
Not that Kettering's initial design was perfect, mind. To get the gearing right, its small pinion gear engaged with the far larger flywheel that featured 25 times the number of teeth. Consequently, if the engine idled at 800rpm, the combined starter and generator would spin at 20,000rpm - and fairly catastrophic failures of the permanently engaged motor were possible as a result.
American automotive pioneer Vincent Hugo Bendix had, in 1912, patented the 'Bendix' starter system. This featured a pinion mounted on a helical drive spring, which would allow for reliable engagement and disengagement of the starter. When the motor was engaged, the pinion would wind out and engage with the flywheel - then, when the motor fired, the pinion would be spun away and out of engagement.
This innovation made the fitment and operation of starting motors far easier and safer; by 1914, GM's own cars were using Bendix-drive starters and it would eventually prevail over all other types.
None of the aforementioned, however, were the first to conceive using electrical power to crank an engine over; Kettering, Bendix - and even Coleman - had all been beaten to the punch by British electrical engineer Herbert Dowsing. As is the case in many modern cars, and as later demonstrated by Coleman in 1901, Dowsing used his electrical expertise to develop a combined starter-generator system for early motor carriages.
It was reportedly tested on an Arnold motor car in 1896, the same year in which Dowsing patented the 'Apparatus for the Application of Electricity to Vehicles Driven By Mechanical Means.' Remarkably, Dowsing's integrated starter-generator system was also mooted to provide assistance to the engine when it was under heavy load.
Presumably, Dowsing's concept was far too ahead of the curve to be either practical or marketable on any scale. This, it seems, was a common trend with his ideas - for example, in 1897 he proposed the remarkable concept of using thermopiles on hot engine components to convert waste heat into electrical energy that could be stored and later deployed via the electric motor assembly - or, as he pointed out, for starting the engine itself.
Regardless, Kettering and Cadillac's self-starting system led the way for the wider acceptance of this now standard creature comfort - a technology that finally made the crank handle disappear and enabled more to easily get out in their cars. 'It was a complete game changer,' says Greg Wallace, director of GM's heritage centre. 'Within a few years, Cadillac featured women in their advertising showing them as drivers, instead of passengers or bystanders. It was one of the most significant innovations in the history of the automobile.'
Gassing Station | General Gassing | Top of Page | What's New | My Stuff