Planetary success for the planetary mixer !
This article first appeared in the 34th issue of the bulletin of the Amicale Calvel.
By Hubert Chiron
Few bakery and pastry making machines were so innovative when they first came out as the vertical three-speed planetary mixer with its three attachments (whip, paddle and hook). One machine could now beat, mix and whip, allowing it to be used in all kinds of food preparation, and even in private homes. This article will help to identify some key dates in its design. One of the centres of innovation seems to have been the USA where, between 1905 and 1908, the Read company electrified the market with its “egg and cake mixer”, which had a gearbox containing a so-called epicyclic or planetary gear train which caused the attachment to follow a planetary path. Then, in 1915, the Hobart company introduced to American bakers a large three-speed mixer with a mechanical gearbox and a power take-off for driving numerous accessories, thus greatly expanding the functions of the machine and making it universal.
Early cranked mixers
In order to understand the various stages through which we have arrived at the machines we use today, it is interesting to see what the very earliest equipment was like. Apparently they were egg beating or jam mixing machines in which the gear wheels were visible. They were
driven either by a hand crank or by pulleys connected by belts to a steam engine or internal-combustion engine.
Arrival of speed-change devices
By belts and cone
Once the earliest egg beater machines had been invented, variable speed drives became necessary in order more accurately to reproduce the actions of human cooks whisking their eggs. The earliest system for varying the speed of the whip without having to stop the machine to change the pulley seems to have been the cone, along which the
belt was slid. Illustrations of this type may be found in etchings of English machines presented at the 1885 Paris Trade Exhibition. It was a slow, rather rustic and often complicated system but was nevertheless sold in France until 1910 (Lanchon catalogue). Speed-change mechanisms with pulley arrangements can be seen in the trade press in the USA from 1904-1906.
Mechanical gearboxes were essential to the development of the first cars. Increasing sales made it feasible to put gearboxes into more applications – such as mixers. Meanwhile, still in the US, the epicyclic transmission gearbox was used in, for example, the celebrated Ford A motorcar (1903) and then in the Ford T (1908). Problems with lubricating the gearboxes of the first mixers also had to be solved. Between 1905 and 1908 Read was the first American company to make a three-speed mixer. The company makes an allusion to this analogy with the car industry a few years later. As early as 1907 there were dough mixers in which all the gears were hidden, as well as two-speed bakers’ dough mixers (Joliet machinery). Numerous patents were granted in this period for simplified gear-change mechanisms.
The Read mixer had a gearbox offering three pre-selected speeds and an epicyclic geartrain which moved the tool in a planetary path. The machine had to be stopped to change the speed, and the drive was still via a pulley and belt. The precision of the planetary movement folded air into creams and frothed egg whites better than had ever been seen before. The machine, supplied with a whip and a flat beater, came out under the name Read’s three speed egg and cake machine. It did not yet have a dough kneading hook. It was not until 1914 that the machine acquired an electric motor on its stand, allowing direct drive. It had a stop/start button on the machine itself, avoiding the risk of accidents due to long drive belts.
By gearbox, while running
Not all makers went the same mechanical route. In 1911, mixers were brought out with progressive speed-changing gearboxes, allowing attachments to be run at variable speeds. This mechanical option, whereby the speed could be changed while the machine was working, was adopted widely in Germany. Meanwhile, Swiss manufacturer Artofex brought out mixing and beating machines with a dual fixing system so that attachments could be mounted either vertically or obliquely. This was followed by combination machines in which a single motor drove two, three or four units (beating, mixing, chopping/slicing, blending).
The Hobart mixer and its power take-off system
The Hobart website dates the invention of its stand mixer (without specifying its size) to 1908 (the inventor was Herbet Johnson). However, as regards the large models designed for bakers and pastry makers, the first advertisement appeared in 1915 in the American magazine The Baker Helper. This was the 280-B model, with the motor enclosed in the housing. Beside its sturdy construction, the main innovation was that the Hobart mixer had a power take-off which could be used to drive multiple tools that were very useful in all areas of food preparation (meat mincer, vegetable chopper, food mill, grinder). At least twenty-one different operations could be performed when the accessories (one was a sharpening wheel!) were connected to the power take-off. In 1919 Hobart brought out its domestic model, the Baker’s Aid, a precursor of the Kitchen Aid products with a small electric motor and interchangeable bowls.
Mixers sold in France
The beginnings in 1922
We have found no signs of advertisements for mixers in France before the year 1922. However, in that year three large manufacturers appear in the Paris bakers’ directory – two American companies (Read and Hobart) and one French (Bouvard). They make much of the great advantage of the planetary movement of the attachments, which helps to produce perfect mixtures and optimises foam expansion.
Pastry chefs snapped them up enthusiastically – no more kneading pasta and brioche by hand! The three attachments, i.e. the whip, the flat beater and the hook, gave the machine a greater range of functions than any previous apparatus. The existing range of these three-speed fitments is 150, 300 and 600 rotations per minute respectively. It is easy to imagine how popular they woud have been with apprentices weary of egg-beating chores. The market was impressive—pastry chefs, confectioners, chocolate makers, biscuit cooks, caterers, restaurateurs. In some biscuit factories one could find lines of ten or more machines!
French manufacturers get in on the act
In the 1930s other French mixer manufacturers got into this growing market—Bonnet in Villefranche, Guoguet Mermet in Romans, and Phébus in Nantes. Hobart was now the unchallenged leader, claiming more than 100,000 machines in 1930, whereas Read had ceased being sold in our country. This was the age of the “all cast iron and steel” mixers that were so heavy to move. And yet despite their having only basic controls, if properly lubricated they gave unfailing service year after year. The capacities of their tin-plated steel bowls varied from 10 to 80 litres, enabling them to be used in every area of food processing. The first wave of installation of these mixers was therefore between the two world wars. Buyers were mostly the large baked goods and pastry manufacturers. Our German neighbours generally chose variable-speed machines like the Rego (1927).
In the early 1950s new models of mixers began to be brought out that were differently sized: smaller, lighter models, and in particular ones that could be stood on a work surface, such as the Pygmée from Phébus (1953). The manufacturer Bouvard offered eight models with bowls from 5 to 100 litres.
Manufacturers Sama of Aubusson (which later became Dito-Sama) was to have spectacular success in 1962 when it introduced its B40 mixer with continuous 8-speed mechanical changes. Speed changing was by a lever which released a trapezoidal belt. The flanges of the pulleys moved apart so the walls could slide, allowing the speed at the input to the planetary box to be changed. The apparatus, built in large numbers, had a multi-speed power take-off to which accessories could be connected. The bowl was stainless steel and could be heated by a stainless steel burner in the base. The motor was protected in case of blockage by temperature probes. The so-called “pigtail” hook prevented soft mixtures rising up the arm.
Other French makers expanded the range (Bonnet offered bowls in sizes from 20 to 150 litres), while keeping the same principle of a three-speed gearbox. They modernised their mixers, made greater use of welded sheet than cast iron, and made their machines quieter.
Thereafter, mixers were equipped with three-speed electric motors which drove the mixer’s planetary gearbox either directly or via a fixed step-down ratio (belt and pulley). On the plus side this meant the operator did not have to stop the machine in order to change the speed; but it also meant the machine had little protection from current spikes.
More recently we have seen mixers with electric variable-speed drives. In this case, a single-speed motor connected to an electronic variable speed drive directly drives the mixer’s planetary gearbox via a fixed-ratio belt-and-pulley speed reducer. This system allows not only three fixed speeds, which is useful for consistent working, but also an infinite range of rpm to adapt to different products. Overload and overcurrent protection is available, and the machine allows soft starts and soft stops.
Ergonomics, safety and hygiene
Since the 1980s and 1990s, manufacturers have applied the machinery directive which is designed to ensure user safety. They equip their models with safety screens and bowl-raised position sensors. Lifting levers have also been given power assistance to reduce effort. In the 21st century, the particular challenges of food processing require a move to an all-stainless steel environment for machines in food processing areas.
Over the last ten years, manufacturers have mostly concentrated their efforts on industrialisation, i.e. more extensive use of automatic control systems (pre-programmed phase sequencing), mobility and cleanability.