Abstract: A power takeoff mechanism for a farm tractor with two interchangeable power takeoff shafts which can be driven at different speeds and are connected by means of annular flanges of different diameters with a driving flange on the end of an output shaft wherein a pawl is pivoted near the driving flange and is connected to a clutch lever of the gear shifting mechanism whereby the pawl must be pivoted to a predetermined position when one of the power takeoff shafts is installed, thereby preventing the clutch lever from being operated in a manner to select an inappropriate speed for the installed power takeoff shaft.

Abstract: A change-speed gear in group-type construction with a main gear-shifting mechanism and a group gearing connected thereto. A primary shaft drives a main shaft selectively via gears of an intermediate shaft or by direct coupling of the primary shaft and the main shaft and at different speeds. The gears of the main shaft furthermore mesh with gears of the group stages of the group gearing; these latter gears are freely rotatably mounted on an output shaft and can be coupled therewith. To eliminate components and to provide a compact change-speed gear, one gear of the intermediate shaft, in addition to its function as shifting gear of the main gear-shifting mechanism, at the same times performs the function of a reversing gear for the reverse group of the group gearing.

Abstract: A synchronizing device for a transmission, with pocket-like recesses being arranged on those elements, preferably in the clutch- and/or synchronizing ring, which effect synchronization for improved lubrication and cooling of the friction surfaces. The recesses are continuously supplied with oil from a lubricant circuit via an adjoining annular chamber and bores of a shaft carrying the synchronizing device and opening into the annular chamber.

Abstract: Transmission with double friction clutch, especially transmission for agricultural and/or vehicles for the construction industry, with two gear shifting groups, each one of which can be shifted by means of an associated clutch, with the groups being shiftable under load. One of the clutches is engaged by being spring-biased and engageable by means of a selectively acting pressure medium adapted to operate one or several cylinder/piston units. The effective operating surface of the pertaining piston is greater than the operating surface of the piston associated with the second clutch. The cylinders are connectible in such a way that on each piston in each shift position thereof the same shifting pressure is exerted.

Abstract: A transmission constructed in groups with shiftable clutches to vary the ratio and the direction of the drive and including clutches shiftable under load. The arrangement of the clutches shiftable under load is such that a selective shifting under load from forward to rearward drive or from slow forward drive to fast forward drive, and vice versa, will be possible after preselecting a forward or a reversing transmission.

Abstract: A power take off, especially for an agricultural or construction type vehicle, in which an input shaft and an output shaft have a train of meshing gears extending therebetween with a normally disengaged friction clutch having input and output parts interposed between the input shaft and the first gear of the train. A brake is provided having a brake body normally engaging the output part of the friction clutch. The brake structure is supported in a stationary tubular element which also forms the journal means for another gear of the series of meshing gears. Fluid operable means are provided for actuating the clutch toward engaged position and the brake toward disengaged position.

Abstract: A change gear transmission of the group design, especially for vehicles for agriculture and construction with a group transmission following a velocity control transmission the output shaft of which is arranged parallel to a main shaft. This main shaft is provided with gears connected to the main shaft for rotation therewith. The main shaft is driven through the intervention of a counter shaft of the velocity control transmission, which counter shaft is parallel to the main shaft. The counter shaft is through an input transmission continuously frictionally connected to the input shaft which latter is adapted by a clutch element in a direct velocity stage to be coupled to said main shaft. All gears of the main shaft mesh directly or indirectly with gears freely rotatable on said counter shaft and output shaft respectively.

Abstract: A transmission for connecting a prime mover with a load, such as vehicle wheels, in which the transmission is of group construction with a primary group shiftable under load and at least one other group which is not shiftable under load. The group shiftable under load provides for at least two forward speeds and a reverse speed at the main output shaft of the transmission which supplies the power to the load.