AU2614602A - Transport vehicles - Google Patents

Description

P/00/011 Regulation 3.2 COMMONWEALTH OF AUSTRALIA Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant: Actual Inventor(s): Address for Service: Invention Title: LIONEL MOORE AHEARN FOX Patent Trade Mark Attorneys GPO Box 1149 Brisbane Queensland 4001 "TRANSPORT VEHICLES" The following statement is a full description of this invention, including the best method of performing it known to me: TRANSPORT VEHICLES THIS INVENTION relates to transport vehicles and in particular to tipper type tri-axle semi-trailers.

Tipper type tri-axle semi-trailers typically are pivoted about the rear most axle and wheel assembly by raising the front end of the trailer relative to the prime mover by a hoist. The other two axle and wheel assemblies are raised from the ground with the trailer chassis or main frame and thus do not support the trailer at all when in the raised attitude. Such types of trailer are generally less stable than desired and it is not uncommon for them to tip over. Consequently they cannot be safely used for transporting some goods. In some cases, for example, the transportation of heavy waste material, tri-axle trailers cannot be used because of government safety requirements. In such cases, 15 tandem-axle trailers are used in which the trailer deck pivots about a laterally extending axis intermediate the tandem axles upon raising of the front end of the trailer. While such trailers provide greater stability than the aforementioned tri-axle trailers, they cannot carry the same amount of load and in Australia are typically limited to about 16.5 tonnes while tri-axle trailers can carry up to 22 tonnes. Alternatively, non-articulated trucks are used with the resulting lower carrying capacity.

The present invention is aimed at providing a transport vehicle and semi-trailer which can carry a greater load than tandem axle trailers but which has better stability while tipping than the presently available tri-axle trailers of the aforementioned type.

In one aspect the invention resides broadly in a tipper semitrailer, including: a wheeled bogie having a first sub-frame and first and second spaced apart axle and wheel assemblies arranged in tandem, each of said first and second axle and wheel assemblies being operatively connected to said first sub-frame for up and down movement relative thereto; a longitudinally extending frame assembly adapted to support thereon a load or deck mounted near its rear end to said first subframe intermediate said first and second axle and wheel assemblies for up and down pivoting movement of said frame assembly relative to said first sub-frame about a pivot axis extending generally parallel to said axle and wheel assemblies between a lowered attitude in which the semi-trailer is adapted for road travel and a raised attitude in which the semi-trailer is adapted to discharge a load rearwardly therefrom; a third axle and wheel assembly operatively connected to said frame assembly for up and down movement relative thereto forward of said wheeled bogie; securing means for selectively securing said first sub-frame to said frame assembly so as to prevent movement of said first subframe relative to said frame assembly; each of said first, second and third axle and wheel assemblies being supported by fluid type suspension means at or near each end 15 and said fluid type suspension means at each side of said frame assembly being in fluid communication with each other so as to share the load between said first, second and third axles.

Preferably, said first and second axle and wheel assemblies depend from said first sub-frame and said pivot axis is centred between the rotational axes of the first and second axle and wheel S• assembles thereby providing greater stability of the semi-trailer while tipping.

Preferably, said third axle and wheel assembly is mounted to a second sub-frame which is rigidly connected to or integral with said frame assembly. In such form it is also preferred that said second sub-frame be aligned vertically and longitudinally with said first sub-frame when said frame assembly is in the lowered attitude and depends from said frame assembly.

Preferably, said first sub-frame is adapted to be secured to said second sub-frame and securing means are provided for selectively securing said first sub-frame to said second sub-frame.

In a preferred form said securing means includes hydraulic pins mounted on said second sub-frame and complementary apertures in said first sub-frame adapted to receive therein said hydraulic pins to secure said first sub-frame to said second sub-frame.

-3- Preferably, each said axle and wheel assembly is secured to a support bar which is pivotally mounted at one end to a hanger depending from the sub-frame forward of the respective axle and wheel assembly and supported by an air bag (or other suitable fluid suspension device) at the other end. Suitably, the three air bags on each side of the trailer are in fluid communication with each other thereby creating an equalizing suspension on each side of the trailer and may be connected so as to be in fluid communication with the air bags on the other side if desired.

In another aspect the invention resides broadly in a transport vehicle, including: a prime mover; a semi-trailer operatively connected at its front end to said prime mover, said semi-trailer including a wheeled bogie having a first sub-frame and first and second spaced apart axle and wheel 15 assemblies arranged in tandem, each of said first and second axle and wheel assemblies being operatively connected to said first subframe for up and down movement relative thereto, a longitudinally extending frame assembly adapted to support thereon a load or deck mounted near its rear end to said first sub-frame intermediate said first and second axle and wheel assemblies for up and down pivoting S• movement of said frame assembly relative to said first sub-frame about a pivot axis extending generally parallel to said axle and S wheel assemblies between a lowered attitude in which the semtrailer is adapted for road travel and a raised attitude in which the semi-trailer is adapted to discharge a load rearwardly therefrom, a third axle and wheel assembly operatively connected to said frame assembly for up and down movement relative thereto forward of said wheeled bogie, and securing means for selectively securing said first sub-frame to said frame assembly so as to prevent movement of said first sub-frame relative to said frame assembly, each of said first, second and third axle and wheel assemblies being supported by fluid type suspension means at each end and said fluid type suspension means at each end being in fluid communication with each other so as to share the load between said first, second and third axles; a hoist operatively connected to said semi-trailer for raising and lowering the front end relative to said prime mover so as to pivot said frame assembly about said pivot axis.

In yet another aspect the invention resides broadly in a method of converting a tandem axle tipper semi-trailer to a triaxle tipper semi-trailer, the tandem axle semi-trailer having a longitudinally extending frame assembly adapted to support thereon a load or deck, including: removing the tandem axle and wheel assemblies from the frame assembly of the tandem axle semi-trailer; providing a wheeled bogie having a first sub-frame and first and second spaced apart axle and wheel assemblies arranged in tandem, each of said first and second axle and wheel assemblies being operatively connected to said first sub-frame for up and down movement relative thereto, each of said first and second axle and 15 wheel assemblies being supported by fluid type suspension means at each end; 99 mounting said longitudinally extending frame assembly near its rear end to said first sub-frame intermediate said first and second axle and wheel assemblies for up and down pivoting movement of said 20 frame assembly relative to said first sub-frame about a pivot axis 9. 9.

e S• extending generally parallel to said axle and wheel assemblies between a lowered attitude and a raised attitude; providing a second sub-frame having a third axle and wheel assembly operatively connected thereto for up and down movement relative to said second sub-frame, said third axle and wheel assembly being supported by fluid type suspension means at each end; mounting said second sub-frame rigidly to said frame assembly forward of said first sub-frame with said third axle and wheel assembly generally parallel to said first and second axle and wheel assemblies; providing securing means on said first and second sub-frames for selectively securing said first sub-frame to said second subframe so as to prevent movement of said first sub-frame relative to said frame assembly; and connecting the fluid type suspension means of said first, second and third axle and wheel assemblies at each end together being in fluid communication with each other so as to share the load between said first, second and third axles.

In yet another aspect the invention resides broadly in a method of converting a tandem axle tipper semi-trailer to a triaxle tipper semi-trailer, the tandem axle semi-trailer having a longitudinally extending frame assembly adapted to support thereon a load or deck, the frame assembly being supported by a wheeled bogie having a first sub-frame and first and second spaced apart axle and wheel assemblies arranged in tandem, each of said first and second axle and wheel assemblies being operatively connected to said first sub-frame for up and down movement relative thereto, each of said first and second axle and wheel assemblies being S..o supported by fluid type suspension means at each end; 15 providing a second sub-frame having a third axle and wheel assembly operatively connected thereto for up and down movement relative to said second sub-frame, said third axle and wheel *o assembly being supported by fluid type suspension means at each end; mounting said second sub-frame rigidly to said frame assembly Sforward of said first sub-frame with said third axle and wheel assembly generally parallel to said first and second axle and wheel S assemblies; providing securing means on said first and second sub-frames for selectively securing said first sub-frame to said second subframe so as to prevent movement of said first sub-frame relative to said frame assembly; and connecting the fluid type suspension means of said first, second and third axle and wheel assemblies at each end together in fluid communication with each other so as to share the load between said first, second and third axles.

In order that the invention may be more clearly understood and put into practical effect, reference will now be made to the accompanying drawings wherein: Fig. 1 is a diagrammatic side elevation of a semi-trailer -6according to the present invention in the lowered attitude with some parts omitted for clarity; Fig. 2 is an expanded view of part of the sem-trailer of Fig.

1 showing the rear end portion of the semi-trailer more clearly; Fig. 3 is a diagrammatic side elevation of the semi-trailer of Fig. 1 in the raised attitude with some parts omitted for clarity; Fig. 4 is an expanded view of part of the semi-trailer of Fig.

1 showing the rear end portion of the semi- trailer more clearly in the raised attitude; and Fig. 5 is a diagrammatic plan view of the wheeled bogie of the semi-trailer of Fig. 1.

The semi-trailer 10 illustrated in Fig. 1 includes a longitudinally extending frame assembly (or frame) 11 which is supported on three spaced apart axles 12(rearmost), 15 13(intermediate) and 14(foremost) located beneath the rear end portion of the frame assembly to which dual wheel sets 20a, 20b and are connected in the usual manner as shown in Fig. 5 to form axle and wheel assemblies. The rear and intermediate axle and wheel assemblies are mounted to and depend from a sub-frame 15 as will 20 be described in more detail later, to form a wheeled bogie 17 while the foremost axle and wheel assembly is mounted to a separate subframe 16 forward of the bogie sub-frame as will also be described in more detail later.

The frame assembly 11 has two spaced apart longitudinally 25 extending frame members lla and llb joined by a plurality of cross members to form a chassis in known manner. Two spaced apart side plates 18 and 19 depend respectively from the frame members lla and llb and are connected at their lower ends by a base plate 21 to form a mounting box 20 and a pivot bush 22 is secured to the base plate with its axis extending generally parallel to the axles 12, 13 and 14. Two complementary side plates 23 and 24 depend in like manner from the bogie sub-frame outside the mounting box and a pivot pin 26 extends through aligned apertures 27 and 28 in the bogie sub-frame side plates and the pivot bush to pivotally connect the frame assembly to the bogie for tipping the frame assembly -7relative thereto about pivot axis 29 parallel to the axles. It will be seen that the pivot axis is centred between the rear axle and the intermediate axle and is below the axle height which advantageously increases the stability of the semi-trailer while being raised by the hoist assembly 30 shown in Fig. 1 for tipping the semi-trailer about the pivot axis 29 to unload the semi-trailer rearwardly.

The forward sub-frame 16 is rigidly mounted to the frame assembly 11 by a pair of spaced apart side plates 31 and 32 which depend from the frame members lla and 11b respectively. A pair of hydraulic extendable and retractable pin assemblies are mounted to the forward sub-frame and are adapted to selectively engage with complementary locating bushes secured to the bogie sub-frame to lock the two sub-frames together for road travel as a tri-axle trailer or to release the two sub-frames from each other so that 15 the frame assembly 11 can tip about the pivot axis 29 while being supported by the bogie axles (the rear and intermediate axles)and their respective wheels, while the forward sub-frame and the forward axle 14 and its wheel assemblies are raised with the frame S assembly as shown in Figs. 3 and 4. The hydraulic pin assemblies are connected to a hydraulic pump via a control valve operated from the cab of the prime mover and a sequencing valve which prevents the hoist assembly from raising the frame assembly unless the hydraulic pins are retracted (disengaged) to allow the forward subframe and attached foremost axle to lift with the frame assembly S: 25 as illustrated in Fig.3.

As can be seen in Fig. 2, the rear axle 12 is mounted adjacent each of its ends to a support arm 41 which in turn is pivotally mounted in a hanger 42 at its forward end for up and down pivoting movement relative to the bogie sub-frame and at its rearward end to an airbag 43 adapted to carry the axle load in known manner similar to a leaf spring suspension system. The intermediate axle 13 is mounted in the same manner forward of the rear axle by arm mounted in hanger 46 at its forward end and to airbag 47 at its rearward end. The forward axle 14 is also mounted in a similar manner but to the forward sub-frame 16 with its forward end mounted -8in hanger 50 and rearward end to airbag 51. Downward pivoting movement of each of the three arms 41, 45 and 49 on each side of the frame assembly is limited by respective stopper rods (not shown) in order to protect the airbags from over extension. The three airbags are in fluid communication with each other via fluid lines 56,57 and 58 so that the pressure in the airbags can be equalised during travel to share the load between the three airbags on each side of the semi-trailer.

It will be appreciated that when the hydraulic pins are moved to the retracted position and the frame assembly hoisted to the raised attitude to tip a load rearwardly, the airbags remain in fluid communication with each other and the load is equalised between the rear axle and the intermediate axle with the forward axle being raised and taking no load.

In use, the semi-trailer is hitched to a prime mover in the 15 normal manner at hitch pin 61. For road travel, the hydraulic pins 36 and 37 on each side of the frame assembly are engaged so that the bogie sub-frame 15 is rigidly secured to the forward sub-frame 16 and thereby to the frame assembly 11 so that the semi-trailer can operate as a tri-axle trailer with the load being equalised between the three axles via the airbags 43, 47 and 51. Equalisation of the load is achieved via fluid transfer through the fluid lines 56, 57 and 58 in known manner for airbag suspension systems. If desired, additional fluid transfer lines can be provided so that fluid can be transferred to the three corresponding airbags at the other side of the frame assembly, those three airbags being arranged in the same manner.

In order to tip the trailer, the hydraulic pins are moved to the retracted position by operating a controller in the cabin of the prime mover. Once the hydraulic pins have been retracted, the hoist can be operated in known manner to tip the semi-trailer whereupon the frame assembly pivots about pivot axis 29 and the load is equalised between the rear axle and the intermediate axle.

The forward sub-frame and the attached forward axle are raised with the frame assembly and the airbags 51 remaining in fluid communication with the airbags 43 and 47 although no load is being -9carried by the forward axle during tipping.

Various modifications of the invention are contemplated which will be apparent to persons skilled in the art, and which can be resorted to without departing from the spirit and scope of the invention as defined in the appended claims.

*e **o*9e

Claims (18)

1. A tipper semi-trailer, including: a wheeled bogie having a first sub-frame and first and second spaced apart axle and wheel assemblies arranged in tandem, each of said first and second axle and wheel assemblies being operatively connected to said first sub-frame for up and down movement relative thereto; a longitudinally extending frame assembly adapted to support thereon a load or deck mounted near its rear end to said first sub- frame intermediate said first and second axle and wheel assemblies for up and down pivoting movement of said frame assembly relative to said first sub-frame about a pivot axis extending generally parallel to said axle and wheel assemblies between a lowered attitude in which the semi-trailer is adapted for road travel and 15 a raised attitude in which the semi-trailer is adapted to discharge a load rearwardly therefrom; a third axle and wheel assembly operatively connected to said frame assembly for up and down movement relative thereto forward of said wheeled bogie; 20 securing means for selectively securing said first sub-frame to said frame assembly so as to prevent movement of said first sub- frame relative to said frame assembly; each of said first, second and third axle and wheel assemblies .being supported by fluid type suspension means at or near each end and said fluid type suspension means at each side of said frame assembly being in fluid communication with each other so as to share the load between said first, second and third axles.

2. A tipper semi-trailer according to Claim 1, wherein said first and second axle and wheel assemblies depend from said first sub- frame and said pivot axis is centred between the rotational axes of the first and second axle and wheel assembles.

3. A tipper semi-trailer according to Claim 2, wherein said pivot axis is also centred below the rotational axes of the first and -11- second axle and wheel assembles.

4. A tipper semi-trailer according to any one of the preceding claims, wherein said third axle and wheel assembly is mounted to a second sub-frame which is rigidly connected to or integral with said frame assembly.

A tipper semi-trailer according to Claim 4, wherein said second sub-frame depends from said frame assembly.

6. A tipper semi-trailer according to Claim 5, wherein said second sub-frame is aligned vertically and longitudinally with said first sub-frame when said frame assembly is in the lowered attitude.

7. A tipper semi-trailer according to any one of Claims 4, 5 and S 6, wherein said first sub-frame is adapted to be secured to said second sub-frame. S*

8. A tipper semi-trailer according to Claim 7, including securing 20 means for selectively securing said first sub-frame to said second sub-frame.

9. A tipper semi-trailer according to Claim 8, wherein said securing means includes hydraulic pins mounted on said second sub- 25 frame and complementary apertures in said first sub-frame adapted to receive therein said hydraulic pins to secure said first sub- frame to said second sub-frame.

A tipper semi-trailer according to any one of the preceding claims, wherein each said axle and wheel assembly is secured at its opposite ends to a support member, each support member being pivotally mounted at one end to a complementary hanger depending from the respective sub-frames forward of the respective axle and wheel assemblies and supported by said fluid type suspension means at the other end. -12-

11. A tipper semi-trailer according to any one of the preceding claims, wherein each of said fluid type suspension means is an air bag suspension device.

12. A tipper semi-trailer according to any one of the preceding claims, wherein the fluid type suspension means on one side of said frame assembly are in fluid communication with the fluid type suspension means on the other side of said frame assembly.

13. A transport vehicle, including: a prime mover; a semi-trailer operatively connected at its front end to said prime mover, said semi-trailer including a wheeled bogie having a first sub-frame and first and second spaced apart axle and wheel assemblies arranged in tandem, each of said first and second axle and wheel assemblies being operatively connected to said first sub- frame for up and down movement relative thereto, a longitudinally extending frame assembly adapted to support thereon a load or deck S. mounted near its rear end to said first sub-frame intermediate said 20 first and second axle and wheel assemblies for up and down pivoting movement of said frame assembly relative to said first sub-frame about a pivot axis extending generally parallel to said axle and wheel assemblies between a lowered attitude in which the sem- trailer is adapted for road travel and a raised attitude in which the semi-trailer is adapted to discharge a load rearwardly therefrom, a third axle and wheel assembly operatively connected to said frame assembly for up and down movement relative thereto forward of said wheeled bogie, and securing means for selectively securing said first sub-frame to said frame assembly so as to prevent movement of said first sub-frame relative to said frame assembly, each of said first, second and third axle and wheel assemblies being supported by fluid type suspension means at each end and said fluid type suspension means at each end being in fluid communication with each other so as to share the load between said first, second and third axles; -13- a hoist operatively connected to said semi-trailer for raising and lowering the front end relative to said prime mover so as to pivot said frame assembly about said pivot axis.

14. A method of converting a tandem axle tipper semi-trailer to a tri-axle tipper semi-trailer, the tandem axle semi-trailer having a longitudinally extending frame assembly adapted to support thereon a load or deck, including: providing a wheeled bogie having a first sub-frame and first and second spaced apart axle and wheel assemblies arranged in tandem, each of said first and second axle and wheel assemblies being operatively connected to said first sub-frame for up and down movement relative thereto, each of said first and second axle and wheel assemblies being supported by fluid type suspension means at Seach end; mounting said longitudinally extending frame assembly near its rear end to said first sub-frame intermediate said first and second axle and wheel assemblies for up and down pivoting movement of said frame assembly relative to said first sub-frame about a pivot axis extending generally parallel to said axle and wheel assemblies 20 between a lowered attitude and a raised attitude; providing a second sub-frame having a third axle and wheel assembly operatively connected thereto for up and down movement relative to said second sub-frame, said third axle and wheel assembly being supported by fluid type suspension means at each end; mounting said second sub-frame rigidly to said frame assembly forward of said first sub-frame with said third axle and wheel assembly generally parallel to said first and second axle and wheel assemblies; providing securing means on said first and second sub-frames for selectively securing said first sub-frame to said second sub- frame so as to prevent movement of said first sub-frame relative to said frame assembly; and connecting the fluid type suspension means of said first, second and third axle and wheel assemblies at each end together in -14- fluid communication with each other so as to share the load between said first, second and third axles.

A transport vehicle, including a prime mover and a semi- trailer according to any one of Claims 1 to 12

16. A semi-trailer as hereinbefore described with reference to the accompanying drawings.

17. A transport vehicle as hereinbefore described with reference to the according drawings.

18. A method of converting a tandem axle tipper semi-trailer to a tri-axle tipper semi-trailer, the tandem axle semi-trailer having a longitudinally extending frame assembly adapted to support thereon a load or deck, the frame assembly being supported by a wheeled bogie having a first sub-frame and first and second spaced apart axle and wheel assemblies arranged in tandem, each of said first and second axle and wheel assemblies being operatively connected to said first sub-frame for up and down movement relative 20 thereto, each of said first and second axle and wheel assemblies being supported by fluid type suspension means at each end; providing a second sub-frame having a third axle and wheel assembly operatively connected thereto for up and down movement relative to said second sub-frame, said third axle and wheel S 25 assembly being supported by fluid type suspension means at each end; mounting said second sub-frame rigidly to said frame assembly forward of said first sub-frame with said third axle and wheel assembly generally parallel to said first and second axle and wheel assemblies; providing securing means on said first and second sub-frames for selectively securing said first sub-frame to said second sub- frame so as to prevent movement of said first sub-frame relative to said frame assembly; and connecting the fluid type suspension means of said first, second and third axle and wheel assemblies at each end together in fluid communication with each other so as to share the load between said first, second and third axles. Dated this 1 9 t h day of March, 2002 LIONEL MOORE By his Patent Attorneys AHEARN FOX