US3394641A - Road roller - Google Patents

Description

F. E. STECK ROAD ROLLER July 30, 1968 Filed March 25. 1967 INVENTOR 1 lixJmmuc/ 15m: ick

United States Patent 3,394,641 ROAD ROLLER Ferdinand Edgar Steck, Bowil, Switzerland Filed Mar. 3, 1967, Ser. No. 620,518 Claims priority, application Switzerland, Mar. 18, 1966, 3,924/66 5 Claims. (Cl. 94-50) ABSTRACT OF THE DISCLOSURE A road roller of the type in which both the front and rear rollers are driven and wherein the support means for the front roller is pivotable about a vertical axis with respect to the support means for the rear roller, such pivotable movement preferably being carried out through the agency of a suitable steering or guide mechanism. A suitable drive motor provides drive means for the front and rear rollers According to one aspect of the invention a drive connection is incorporated between such front and rear rollers and includes a bevel gear drive. Such bevel gear drive embodies at least two bevel gears which are pivotably mounted for movement relative to one another about the aforementioned vertical axis even under load, and wherein such vertical axis at least approximately coincides with a common tangent taken through both of the pitch circles of said bevel gears.

Background of the invention The present invention has reference to an improved road roller of the type wherein both the front as well as also the rear roller are driven, and furthermore, wherein the bearing support for the front roller is pivotable relative to the bearing support of the rear roller about a vertical axis by means of a suitable steering mechanism.

Road rollers of the above-mentioned general type are already known to the art. In prior art constructions of such type road rollers the important advantage of the steerability of the front roller is only obtained with an exceptionally great constructional expenditure. More precisely, to achieve such maneuverability or steerability there is provided, among other things, in the drive connection between the front and rear rollers a transmission shaft which is rotatable about the steering axis and in order to support such shaft there is further provided a housing which is fixedly connected with the bearing support of one of these two rollers and rotatably connected for movement about the steering axis with the bearing support of the other of these two rollers. A further drawback resides in the fact that the turning or deflection, particularly during standstill, results in considerably loading the members of the drive connection because such a turning or deflection results in a rotation about the vertical transmission shaft, that is to say, an additional rotation of one of both rollers.

Summary of the invention Accordingly, it is a primary object of the present invention to provide an improved construction of road roller which overcomes the aforementioned drawbacks of the prior art structures.

Another, more specific object of the present invention pertains to an improved construction of road roller allowing for positive maneuverability of such road roller with a minimum structural expenditure.

Yet a further significant object of this invention pertains to an improved road roller possessing drive connection means between the driven front and rear rollers thereof and which provide a relatively simple, inexpensive yet highly reliable construction insuring for the required maneuverability of such road roller.

Now, in order to implement these and still further objects of the invention which will become more readily apparent as the description proceeds, the invention contemplates that the drive connection between the forward roller and the rear roller and a drive motor for both such rollers possesses a bevel gear drive. This bevel gear drive has two bevel gears which are pivotable relative to one another about the aforementioned vertical axis even under load, and which vertical axis at least approximately coincides with a common tangent taken through both of the pitch circles of said bevel gears.

According to a preferred manifestation of the present invention one of the bevel gears which are pivotable with respect to one another is seated upon a connection shaft which extends within the bearing support of the front roller substantially parallel to the latter. Further, the other bevel gear is seated upon a transmission shaft which extends in the lengthwise direction of the road roller approximately in the middle thereof. This transmission shaft is mounted at a portion of the bearing support of the rear roller and upon which also a bearing housing is axially non-displaceably mounted for rotation about the axis of rotation of such transmission shaft. The bearing support for the front roller is mounted beneath and above the bevel gear drive at the bearing housing for pivotal movement about the aforementioned vertical axis.

Owing to this construction there is achieved that both of the rollers can readily accommodate themselves to irregularities in the slope of the street, road or the like.

Brief description of the drawing The invention will be better understood, and objects other than those set forth above, will become apparent, when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawing wherein:

FIGURE 1 is an elevational view, partially in longitudinal section, of a preferred embodiment of inventive road roller;

FIGURE 2 is a horizontal cross-sectional view of the road roller of FIGURE 1, taken along the line 11-11 thereof; and

FIGURE 3 is an enlarged view showing a detail of the road roller of FIGURE 2, and specifically both of the bevel gears which are pivotable with respect to one another about a vertical axis.

Description of the preferred embodiment Describing now the drawing, reference numerals 1 and 2 respectively designate the front and the rear roller of the inventive road roller device. The vibrators which are usually mounted in such rollers 1, 2 have been conveniently omitted from the drawing since they do not form subject matter which is part of the present invention, nor are any details thereof necessary for understanding the principles of the invention. Continuing, the front roller 1 is mounted at a bearing support means 3. This bearing support means 3 is mounted at its rear end, which is disposed approximately in the middle of the road roller, at the 10- cations 4 and 5 about a vertical axis AA at the forwardly directed eyelets or lug portions 6a of a bearing housing or body 6. Bearing housing 6 is of essentially sleeve-like configuration and is rotatably mounted, yet axially non-displaceable, upon a forwardly depending cylindrical shoulder portion 7a of a main bearing support means 7. The rear roller 2 is mounted at this bearing support means 7 and an overhang arm or bracket 7b is provided thereat upon which there is mounted a suitable drive motor 8.

Drive motor 8 drives a gear 11 through the agency of a multiple V-belt drive 9 or another suitable drive, and further, through the intermediary of a gear train or reduction gearing 10. Gear 11 is fixedly seated upon a transmission shaft 12 mounted in the main bearing support means 7 in front of the rear roller 2. A chain or sprocket gear 13 and a bevel gear 14 are also fixedly seated upon this transmission shaft 12. Starting from the sprocket gear 13 the drive or motive power is transmitted by means of a chain 15 to a sprocket wheel or gear 16 which is rigidly connected for rotation with the rear roller 2.

The bevel gear 14 meshes with a bevel gear 17 which is fixedly mounted at a transmission shaft 18. This transmission shaft 18 is rotatably mounted in the main bearing support means 7 for rotation about an axis which coincides with the axis of the rotatable bearing of the bearing housing 6 seated on the shoulder 7a of the main bearing support means 7. The drive connection from the drive motor 8 and from the rear roller 2 to the front roller 1, in addition to the already mentioned chain drive 13, 15, 16, the transmission shafts 12, 18 and the pair of bevel gears 14, 17, also further incorporates two continuously meshing bevel gears 19 and 20, a transmission or connection shaft 21 rotatably mounted in the bearing support means 3 in a direction substantially parallel to the axis of the front roller 1, and further a chain drive 2-2, 23 and 24 which corresponds to the previously considered chain drive 13, 15 and 16. The teeth of both of the bevel gears 19 and possess the form depicted in FIGURE 3. Their pitch circles have a common tangent which at least approximately coincides with the vertical axis A-A about which is pivotably mounted the bearing support means 3 at the bearing housing 6.

Pivoting of the bearing support means 3 about the above-mentioned axis AA, and for the purpose of steering the front roller 1, can take place even if the gears 19 and 20 are under load, that is to say, during such time as the road roller is working or otherwise operated. Such pivoting of the bearing support means 3 advantageously takes place by means of a suitable steering or guide mechanism which may incorporate a hydraulic piston and cylinder arrangement 25, the rear end of which is hingedly connected to a lateral overhang arm or bracket 6b of the bearing housing 6 and the front end of which is hingedly connected to the bearing support means 3. This piston and cylinder arrangement 25 is double-acting and is operably connected to a conventional control circuit also having a standard control mechanism which can be conveniently operated by an operator riding upon the road roller and sitting upon a non-illustrated seat arranged approximately adjacent the overhang arm or beam 7b.

With such a turning or deflection of the support means 3 for the front roller 1 the latter for instance assumes the position shown in phantom lines in FIGURE 2. Irrespective of whether such a turning has taken place or not, the entire forward portion, which includes the front roller 1, its bearing support means 3 and the bearing housing 6, can freely rotate about the cylindrical shoulder 7a, in order that this front roller 1 can accommodate itself independently of the rear roller 2 to differences in the slope of the street, road or the like upon which the road roller is being propelled or upon which road work is being undertaken.

Naturally, different modifications can be undertaken with regard to the described and exemplary depicted embodiment, without departing from the spirit and scope of the inventive concepts. For instance, it would be possible to do without the seat and without the mentioned steering or guide mechanism which includes the hydraulic arrangement 25, yet however the one or the other of the support means 3 and 7 would be provided with a wagon shaft or center pole which would be operated or guided by the attendant walking behind the road roller.

While there is shown and described a present preferred embodiment of the invention it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims, Accordingly,

What is claimed is:'

1. A road roller comprising:

a pair of driven rollers, one of which defines a front roller and the other a rear roller;

first support means for rotatably mounting said front roller;

second support means for rotatably mounting said rear roller;

means for mounting said first support means provided for said front roller for pivotal movement about a substantially vertical axis and relative to said second support means;

drive means for driving both said front and rear rollers;

drive connection means cooperating with said drive means and interposed between said front and rear rollers;

said drive connection means incorporating a bevel gear drive having at least two bevel gears which are pivotably mounted for movement relative to one another about said vertical axis even under load, said vertical axis at least approximately coinciding with a common tangent taken through both of the pitch circles of said bevel gears.

2. A road roller as defined in claim 1, wherein said drive means includes drive motor means.

3. A road roller as defined in claim 1, wherein said drive connection means further includes a connection shaft upon which is mounted one of said relatively pivotably mounted bevel gears, said connection shaft extending within said first support means for said front roller in a direction substantially parallel to the latter, a transmission shaft upon which is mounted the other bevel gear, said transmission shaft extending in substantially lengthwise direction of the road roller and approximately in the middle thereof, said second support means for said rear roller including a support portion at which is mounted said transmission shaft, a bearing housing mounted for rotation about the axis of rotation of said transmission shaft and axially non-displaceable upon said support portion, said bearing housing providing said mounting means at which said first support means for said front roller is mounted beneath and above said bevel gear drive for pivotal movement about said vertical axis.

4. A road roller as defined in claim 3, further including steering means for bringing about pivotal movement of said first support means for said front roller about said vertical axis.

5. A road roller is defined in claim 4, wherein said steering means comprises a double-acting piston and cylinder arrangement having one end pivotably connected with said bearing housing and the other end pivotably connected with said first support means for said front roller.

References Cited UNITED STATES PATENTS 2,132,107 10/1938 'Hamm 945O 2,691,927 10/1954- Denton 94-50 X 2,728,277 12/1955 McRae 9450 3,228,312 l/l966 Neidhardt 94-5O 3,326,312 6/1967 Buller 945O 3,339,468 9/1967 Hall 9450 NILE C. BYERS, 111., Primary Examiner.

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