Prologue
In the mid-1920’s, the automotive industry was shaken by a number of crises. As a result, Bosch began to reduce its dependency on this sector. One of the ways the company succeeded in doing this was by developing its own products such as household appliances and power tools.

Small power tools for production purposes
The “Forfex” hair trimmer – brought onto the market in 1928 – was the product that launched today’s power tools division. The “motor-in- the-handle” principle formed the basis for the development of modern power tools.

At first, the steadily increasing need for light, handy devices for use in the production of automotive equipment meant that Bosch’s own requirements were reason enough for further development in the power tools field. In addition to the screwdrivers that replaced the devices with flexible power-transmission shafts used in production processes in the Stuttgart and Feuerbach factories, an electric grinder with a motor in the handle was designed for the finishing and polishing of pressing and die-cutting forms. However, products that were initially created for the company’s own use soon became part of the sales portfolio.

Probably the most significant universal device in the first series of small power tools was the Bosch hand-held motor, which could be used for drilling, milling, and brushing, as well as for grinding and polishing.

1934: The first Bosch hammer in the market
The development of a power tool with its motor in the handle was paralleled by the successful modification and enhancement of a construction hammer developed by a Swedish company. Bosch improved its design so that it continued to function reliably even under continuous stress.

In 1932, the hammer was unveiled at the Leipzig Trade Fair. After many experimental and design improvements, Bosch finally brought the Bosch hammer onto the market in 1934. The company had succeeded in constructing and launching the first electric hammer that could strike and rotate at the same time. It could be used for drilling rock, concrete, and brick, and for pointing, chiseling, and tamping in the construction and installation industry. It was also used for chiseling and riveting in the metalworking industry.

The impact force and impact rate of the Bosch hammer depended on the material being processed. Harder material meant fewer, but all the more powerful, impacts. This first Bosch hammer model was equipped with an impact mechanism where the rotational energy of the motor was converted into impact energy. This principle was the secret of the hammer’s long service life and operational reliability, and finally led to it displacing models with brittle flat-coil springs and toothed gears.

The hammer chisel drill
If you wanted to use the device as a chisel, you simply had to insert the chisel bit into the hammer. A specially designed square-ended shaft for the chisel bit transformed the rotational movement into a forward movement which generated the chisel impact motion. This tool soon became a firm favorite among construction specialists as a hammer chisel drill.

The hammer drill, which then weighed in at around seven kilos, was a valuable tool for renovation work of all kinds, such as adding door openings or cutting chases for cables, water pipes, and gas pipes. With the help of the Bosch hammer, holes could be drilled in hard concrete and brick without the holes breaking away at the edges and without causing damage to the masonry, as was often the case when performing these operations by hand.

Multifunctional uses
The Bosch hammer was also a valuable tool for road construction work, and was used in the rebuilding of the Neue Weinsteige road in Stuttgart. Numerous Bosch hammers were used to chisel out openings for mounting the railings. The tool’s reputation spread quickly, both in Germany and beyond.

The hammer met with international approval, not least because it could even be used where space was limited or in dangerous locations such as suspended scaffolding and ladders.

In addition to making hammering and chiseling work easier and more flexible, electric hammers also offered considerable time and cost savings. For instance, drilling could now be done eight to twenty times faster than by hand. Production of the Bosch hammer continued during the Second World War, though only in makeshift fashion. While production of automotive accessories was a key area of operation for Bosch after the end of the war, hammer production nonetheless soon picked up again as a result of the work of reconstruction following the war.

Further developments
The hammer drills owe their extreme efficiency to the introduction of electro-pneumatic technology in the 1960’s, which marked a key milestone in the hammer’s development.

In the years that followed, the electric hammers became smaller, handier, and more technically sophisticated. After the three and four-kilo hammer drills of the 1970’s, Bosch began series producing the world’s lightest electro-pneumatic hammer drill in 1981. With a drilling capacity of 4 to 14 millimeters diameter in concrete, this light hammer was almost comparable with a three or four kilo hammer drill, but with clear advantages for overhead work because of its weight.

The healthy order books of tradesmen in the modernization and renovation sector and the trend toward facilitating and rationalizing work with high-performance tools in the 1970’s and 1980’s led to a sharp increase in sales of the small hammer drills. Since the end of the 1970’s, hammer drills have been equipped with the SDS-plus tool mounting system, which allows the user to change tools quickly and easily.

SDS originally stood for the German “Steck, Dreh, Sitzt” (plug, turn, secure), but is now used internationally as an abbreviation for “Special Direct System.” Bosch responded to the growing popularity of cordless devices among tradesmen by developing the hammer drill with a rechargeable battery in 1984. Cordless devices complemented the existing product range and were used in places lacking mains or generator power.

In its power tools division, Bosch currently produces a broad spectrum of light (1.8 to 3 kilograms), medium (4 to 5 kilograms), and heavy (6 to 12 kilograms) hammer drills. With the Bosch, Skil, and Dremel brands, Bosch today is one of the world’s largest manufacturers of power tools, accessories, and garden tools for the professional and DIY market.