Background of the invention

The present invention relates to a vehicle and an adjustable undercarriage for the vehicle, as defined in claims 1 and 6. More specifically the vehicle is of a type having a movement carriage mechanism of track drive type. Typically, the vehicle has a superstructure which carries operational equipment, e.g. a boom at the end of which are located work tools.

Prior art

Use of track driven vehicles and various types of associated adjustable undercarriages is well known, but most of them lack satisfactory means for fully adjusting to undulating or hilly terrain where such a vehicle is to operate, e.g. in a forest. At such locations, it is important that the vehicle superstructure can assume a properly levelled posture and that the track drive carriage mechanisms can be adjusted in position to allow proper movement on the ground of the terrain.

US 11091358 discloses a track drive based vehicle which has means for adjusting posture of a vehicle superstructure using hydraulic jacks, the tracks of the vehicle being oscillating/tiltable. GB2489720 discloses a similar vehicle structure.

Further, some prior art vehicles and superstructure levelling apparatus thereof are known from e.g. WO2007139878 and US2003047367.

Other background prior art is known from e.g. AT9639-U, CN103963860, EP2071085, EP3763884, EP2058438, JPH0585424, JPH04353128, JPH07324353, KR20090049808, KR20090047024, US2018072356, US2021267132, US3012624, US3289779, US4650017, US6241263, W02008077168, and WO2016156660.

Summary of the invention

The present invention has as an object to provide a vehicle undercarriage which enables common or mutually independent tilting of the track driven carriage mechanisms, and at the same time provide for levelling of the superstructure, all of which is important for safe vehicle operation.

These two movement aspects can be combined, according to the invention. This results in a vehicle which may have its superstructure at high or low level during operation, and assuming a lowermost level posture during transport. Further, it is made possible to raise the superstructure well above the carriage mechanisms when it is required to obtain a proper levelling of the superstructure, in particular when tilting each or one of the carriage mechanisms.

The novel and inventive features of the present vehicle and its associated adjustable undercarriage device are presented in the independent claims 1 and 6, and with further features appearing from their associated sub -claims, as well as from the detailed description with reference to the attached drawings exhibiting non-limiting embodiments of the invention.

Fig.l is a front perspective view from above and one side of the adjustable undercarriage of the vehicle.

Fig.2 is a front perspective view from above and the other side of the adjustable undercarriage of the vehicle.

Fig.3 is a rear perspective view slightly from above and said other one side of the adjustable undercarriage of the vehicle.

Fig.4 is another front perspective view from above and said one side of the adjustable undercarriage of the vehicle.

Fig.5 is a side view of the vehicle undercarriage seen from said one side and showing one track drive mechanism tilted relative to the other track drive mechanism.

Fig.6 is a perspective rear view of the vehicle undercarriage seen from said one side and showing both track drive mechanisms mutually tilted relative to a reference platform of the undercarriage.

Fig.7 is a side view of the vehicle undercarriage seen from said one side and showing both track drive mechanisms mutually tilted relative to a reference platform of the undercarriage.

Fig.8 is a perspective rear view of the vehicle undercarriage seen from said one side and showing one track drive mechanism tilted relative to the other track drive mechanism, and relative to a reference platform of the undercarriage.

Fig.9 is a simplified diagram of controls and sensors related to adjustment of the undercarriage.

Fig.10 is a simplifies illustration of the vehicle with undercarriage and superstructure installed thereon, but without operational equipment indicated. Detailed description

On Fig.10 there is shown a vehicle 10 configured to carry operational equipment and tools, e.g. a boom and grabbing tools, however the equipment and tools not shown for sake of clarity, is shown on Fig.10, the vehicle 10 comprising a superstructure 11 having a housing 12 for a power plant for the operational equipment, such as compressors for hydraulic or pneumaic fluid, as well as electric power generators to power control equipment and electric motors. Further, there is provided a control cabin 13 for the operator of the vehicle 10.

The undercarriage is labelled 14 and exhibits track drive movement mechanisms 15; 16, and a reference platform 17.

The adjustable undercarriage will now be further described with reference to Figs. 1 - 8.

The adjustable undercarriage 14 has the pair of vehicle movement track drive carriage mechanisms 15; 16. A superstructure supporting connection platform 18 is tiltably linked to the reference platform 17, and jacks 19 - 22 for adjustments of the undercarriage are present, the operation thereof to be further described.

Each track drive movement carriage mechanism 15; 16 is tiltably attached to the reference platform 17 via a respective rotary link 23; 24 to a common beam 25 which is rigidly attached to the reference platform 17 at a rear region thereof.

The reference platform 17 exhibits a first rotary link 26 which is interactive with a second rotary link 27, the first rotary link 26 at a first end thereof being rotary linked to the reference platform 17 about a first pivot shaft 28 extending in a longitudinal direction of the undercarriage 14, and at a second end thereof being rotary linked via the second rotary link 27 to a superstructure supporting connection platform 18 about a second pivot shaft 29 being at 90° to the direction of the first pivot shaft 28.

It will be appreciated that the connection platform 18 is connectable to a swing assembly for controlled rotation of the superstructure 11.

The jacks 19 - 22 are constituted by first and second controllable jacks 19; 20 and third and fourth jacks 21; 22.

Each jack of the first and second jacks 19;20 is at one end is rotary linked to the reference platform 17 and is at a second end rotary linked to a respective track drive movement carriage mechanism 15; 16 at a location spaced in longitudinal direction forward of the front region the reference platform 17. It will be appreciated that the first and second jacks 19; 20 enable either or both of the track drive carriage mechanisms to be tilted relative the reference platform 17. Further, as more clearly noted from viewing Fig. 3, it is noted that the common beam 25 has the configuration of a shallow U. Therefore, when operating the first and second jacks 19; 20 in a syncronized operation, it will be appreciated that the reference platform 17 will not only be lifted at its front region, but also slightly at its rear region, because the beam 25 with its shallow U will rotate slightly about the rotary links 23; 24, thereby causing the rear region of the reference platform 17 and the bottom of the shallow U to rise slightly.

The third and fourth controllable jacks 21; 22 are located at either side region of the connection platform 18, each jack thereof at an upper end being rotary linked to the connection platform 18 and at a lower end being rotary linked to a respective adjacent one 15; 16 of the track drive movement carriage mechanisms forward of the respective rotary links 23; 24 of the beam 25.

Operation of the jacks 21; 22 may cause forward or rearward tilting and/or lateral tilting either way of the connection platform 18 to contribute to levelling of the superstructure 11, and also lifting of the superstructure 11 relative to the track drive movement carriage mechanisms 15; 16.

Viewing the drawings it is seen that the first and second jacks 19; 20 together enable tilting of reference platform 17 and the superstructure 11 in a first longitudinal direction of the vehicle 10. Operation of one of the first and second jacks 19; 20 enables the pair of track drive mmovement carriage mechanisms 15; 16 to assume mutually different inclinations relative to the reference platform 17

The third and fourth jacks 21; 22 provide for tilting of the connection platform 18 in lateral direction of the undercarriage 14 about the first rotary shaft 28 and/or tilting of the connection platform about the second rotary shaft 29 in a longitudinal direction of the undercarriage 14.

As indicated above, it will be recalled that cooperative operation of the first, second, third and fourth jacks 19 - 22 provide for raising and levelling the superstructure above posture(s) of the track drive movement carriage mechanisms 15; 16.

Although not indicated on any of the drawings, it will again be appreciated that the superstructure 11 will in operation carry operational equipment, e.g. a boom at the end of which are located work tools. If the vehicle is to be used for e.g. forestry, the tools could be gripping claws, sawing device, or branch cutting device, although other tools such as grabbing shovels, scraper devices or drilling devices could be some of many. The nature of tools is not a limitation of the invention.

Equipment to control operation and movement of a boom and tools attached to an end thereof is well known prior art technique and has no bearing on the current invention. Further, any rotation of the superstructure 11 relative to the connection platform using a well known rotation apparatus has no bearing on the present invention and will not be discussed.

Fig.9 is a simple diagram to illustrate how the four jacks 19 - 22 may be operated. The solid lines denote hydraulic lines, whereas the dotted lines denote electrical signal lines. A programmable computer 30 is provided and it controls an electronically controlled hydraulic valves block unit 31. The unit selectively connects with the the jacks 19 - 22. Pressurized hydraulic fluid is provided via inlet 32 from the power plant (not shown) inside the housing 12. Electric and hydraulic swivels 33; 35. Suitably operation of the jacks 19 - 22 are made from an operation panel 35 with joystick, push buttons, switches and displays in the cabin 13 of the superstructure 11. Associated with each of the jacks 19 - 22 are suitably provided sensors 36 - 39 to record levelling, piston rod movement of the jacks, angle values, video images etc. The computer may be configured to process the information from the sensors to provide operational guidance to an operator in the cabin 13.