ČSD series M 120.2

Sidecar CDv (different data)
Genre :	CDv
Service mass:	5.4 t
Seats:	32
Standing room:	33
Classes :	3.

ČSD series M 120.2
	M 120.206
Numbering:	M 120.201-226
Number:	26th
Manufacturer:	Tatra Mountains , Kopřivnice
Year of construction (s):	1928
Axis formula :	A1
Gauge :	1435 mm ( standard gauge )
Length over coupling:	9,300 mm
Length:	8,500 mm
Height:	3,640 mm
Width:	2,720 mm
Total wheelbase:	4,220 mm
Service mass:	7.3 t
Top speed:	54 km / h
Installed capacity:	65 hp
Motor type:	TATRA
Motor type:	6 cylinder petrol engine
Rated speed:	1,800 rpm
Power transmission:	mechanically
Brake:	Knorr air brake
Seats:	32
Standing room:	33
Classes :	3.

The ČSD series M 120.2 were two-axle railcars of the former Czechoslovak State Railways ČSD for local rail traffic .

history

In the 1920s, the ČSD felt compelled to oppose the growing competition from road traffic with modern, faster vehicles. After the successful use of benzene-electric railcars in long-distance traffic on the main lines , corresponding vehicles should be used on the local lines.

While the companies ČKD and Škoda mounted road buses on rail chassis for this purpose, Tatra in Kopřivnice ( Nesselsdorf ) developed vehicles for the first time in which a light petrol engine in the middle of the vehicle drove a largely symmetrical car. A prototype vehicle was created in 1927 with the designation ČSD series M 130.0 in one copy. In 1928 the ČSD acquired the first ten railcars with the designation M 120.2 . Test drives were carried out with the M 120.202 on the local line Zadní Třebaň – Lochovice in April 1928, and scheduled operations with the M 120.205 began on May 15, 1928 . At that time the vehicles had a funnel coupling . A total of 26 vehicles in three series were purchased. The last vehicle was put into operation in 1929.

The railcars proved their worth, the maximum speed of 54 km / h enabled a significant increase in travel speed on the intended routes. The fuel consumption of 30 l / 100 km and low maintenance costs made it an economical vehicle.

Tatra developed the railcar concept a little later. As a noticeable difference, the driver's cab was placed in a central pulpit above the engine. These idiosyncratic vehicles , known as tower railcars, were procured by the ČSD in several larger series until the mid-1930s. In addition to the M 120.3 , M 120.4 and M 130.2 series , a narrow-gauge version was put into service as the M 11.0 series .

Some cars were converted into sidecars in 1938, some converted into motorized trolleys. The last car in service is said to have been the M 120.210 , which allegedly did not go out of operation until 1943. The box from the M 120.206 has been preserved in Pardubice . It was restored as a stand object between 2013 and 2017 and can be admired in the Rosice nad Labem station since then . According to the railway friends in Pardubice, the box of a car is in the depot of the National Technical Museum in Prague in Čelákovice .

Vehicle body

Extruded profiles that were connected to one another by cross members and struts were used as the frame. The frame construction proved its worth , all vehicles up to the 130.3 had this construction with two long and two cross members and the framework in the riveted construction. The actual car body was made of wood and bolted to the frame using an iron connection bracket. The outside of the car body was covered with sheet metal, inside with plywood. The floor was made of wood and the inside was covered with felt sheets and linoleum. Spark guards were installed above the brake pads to prevent fires when braking. The roof was made of wood and was covered with plywood on the inside and a roof screen on the outside. The passenger compartment had three large and two small lowerable windows on each side. In total, the railcar had 32 seats and 33 standing places. The wooden slatted seats were arranged in a 3 + 1 arrangement. The luggage racks with nets were attached along the wall of the car. Simple air shafts above the compartment windows were used to ventilate the car body.

The two driver's cabs were separated from the passenger compartment by partition walls with sliding doors, with the driver sitting in the middle. Passengers first entered the driver's cab via two outward-opening revolving doors and then through the sliding door into the passenger compartment. At the entrances there were long running boards that were supposed to enable the driver to climb over to the sidecar while driving. From the ČSD series M 120.3 , the transition was in the middle with hinged metal sheets and transition protection; this arrangement was not possible with the M 120.2 due to the middle driver's cab. The interior lighting of the car was provided by electric light bulbs. Electricity was generated by a dynamo , which charged the vehicle's batteries.

The two axles were on roller bearings. One of them was connected to the engine and gearbox with a cardan shaft. The axles were made of chrome-nickel steel , the wheels made of mild steel. Soft leaf springs were used to cushion the car body. The simple central buffer coupling was designed as a funnel coupling . Braking was carried out by an indirect brake from Knorr and a handbrake that acted as a parking brake. The inner shoe brake with asbestos lining acted on the brake discs of both axles.

The exterior paintwork of the railcars and sidecars was originally dark green, the roof gray, frame and chassis black. The interior was ash-colored and the ceiling was painted white. From around 1930 the rail buses on the local and branch lines were given a light green / beige exterior paint for better visibility, as is still known today on the M 120.417 .

engine and gears

The water-cooled six-cylinder Tatra petrol engine was installed under the floor. The engine had an output of 65 hp at 1800 rpm. The power was transferred from the engine via a change gear to a cardan shaft, which drove the drive axle via a bevel gear. This bevel gear drive was designed as a reversing gear. The direction of travel was changed by pivoting the drive bevel gear on one of the two bevel gears connected to the axle. There was a releasable clutch between the engine and the gearbox. A linkage that was operated by a shift lever was used to switch the corresponding gear. There were four speed levels. The speed levels were also changed using a pivoting gear.

The radiator was located on the roof, and a thermostat regulated the engine coolant temperature. The cooling water was cooled down by the head wind. In addition, a fan was installed on the engine to provide additional cooling for the engine block. A Scintilla starter was used to start the engine, but the engine could be started with a hand crank.

To operate the railcar, a starter, driver's brake valve , gas lever, sand spreader, gear lever and control instruments for monitoring the operating conditions were installed on each driver's cab . The railcar had a fuel supply of 150 liters. This was mounted under the floor in a container next to the engine.

sidecar

In 1928, several sidecars were delivered to match the railcars, the external dimensions of which were similar to the railcars. The sidecars had 28 seats in a 2 + 2 arrangement.