DESC:FIELD OF INVENTION
The present invention generally relates to a field of mechanical and automobile engineering and particularly to the field of concrete mixing devices/machines. The present invention specifically relates to the self-loading concrete mixing machines.
BACKGROUND OF THE INVENTION
The civil engineering sector from the past century has changed the world of construction and architecture to a different stage due to advancements in construction techniques. Concrete being a fundamental mixture in the field of construction has been prepared in different manners by different constructional engineers such as the quantity of water in a mixture of cement and sand along with aggregates (small stones). Conventionally the concrete was being prepared by manual operation of labor using shovel and the like and then came the concrete mixers where the labors were specified to add specific amount of cement, sand, and water. This was a tough job for the labor and more importantly very much time consuming and eventually costly.
With the advancements in automobile sector, there came self-loading concrete mixers which would collect the sand, cement, gravel and water and fed it to the mixing drum of the mixer. These self-loading mixers were a mile-stone for the constructional companies as the cost of labor reduced and the time to prepare a mixture also reduced which therefore reduced the time to build any structure. The self-loading concrete mixer (SLCM) is a mobile batching plant on wheels which is equipped with a mixing drum, loading arm & bucket & various other components for the production of high-quality concrete. It offers complete independence for the production & transportation of concrete than any other loading & transportation devices for concrete production.
The self-loading mixers are operated c in manner that the required hydraulic/electrical actuation of said mixing from charging to discharging is controlled through the front cabin. The said actuation is powered by the same engine through which the conventional self-loading concrete mixer runs over road or performs necessary steering functions. Therefore, these conventional SLCM vehicles are run through a heavy large displacement single IC engine for various operations which has more torque and horsepower. So, when said conventional self-loading concrete mixer is driven to a specific location & is stationary, the steering/travel function are not in operation, but the main engine is kept in running condition in order to perform mixing operations, thus leads to unnecessary usage of power, as all the hydraulic pumps of SLCM are coupled to single IC engine, similarly when the SLCM is moved from one place to another after completion of work or travel return after discharge of concrete, the travel pump coupled to engine alone is required and employed, but other hydraulic pumps are also functional since the same are connected in series with the engine, this increases the fuel consumption and heats up the oil unnecessarily & reduces the pumps life & associated parts life.
The vehicle response during empty travel is poor, since all the pumps are always functional and consuming power from engine. The cost of large displacement single IC engine is more than two lesser displacement small IC engines. Nowadays large displacement IC engines uses electronic fuel injection system which require expensive maintenance and skilled labor for service/repair which increases the overall cost of vehicle. The noise & vibration of large displacement single IC engine is always high.
There are a number of short comings of conventional SLCMs as discussed above, hence there exists a need for a Self-Loading Concrete Mixer (SLCM) which will overcome the shortfalls of conventional SLCMs.
SUMMARY OF THE INVENTION
The present invention relates to a twin-engine self-loading concrete mixer employing at least two IC engines with a first one for travel and steering operations in order to drive a vehicle/mixer from place to place and a second engine for performing concrete mixing and delivery operations. In the present invention, a need based operation/ operation specific engine configuration is possible. For example, vehicle mobility is independently performed by travel pump and motor configuration which is coupled with a gear box, propeller shaft, axle unit and tyres.
In an embodiment of the present invention a twin-engine self-loading concrete mixer comprising: a housing/ bonnet disposed over a chassis of a vehicle and configured to enclose at least a pair of IC engines, wherein said housing is fixed over said chassis as protective enclosure for said engines mounted on said vehicle chassis, wherein said chassis/frame comprises of a plurality of steel tubes welded together in a manner to hold an overall weight of said vehicle, wherein said housing is configured to be detachably attached over said vehicle chassis in order to perform maintenance and inspection necessary for said vehicle operation; an operator cabin disposed over said chassis of said vehicle besides said housing and parallel to it, wherein said operator cabin comprises an operator compartment with a steering system and a plurality of control modes in order to mobilize said vehicle and perform intended functions, wherein said steering system is configured to be powered through a first engine, wherein said operator compartment is configured to perform a swivel function with at least 180 degrees swivel along a vertical axis with said compartment when swivel in forward direction, said vehicle is configured to be driven on road and with said compartment being in backward direction, said vehicle is configured to perform site operations.
Another embodiment of the invention states an independent braking unit disposed within said operator cabin and fixed over axles for each wheel of said vehicle, wherein said braking unit comprises at least four brakes and is configured to provide a single pedal operation via a master cylinder from said cabin and thereby actuate said at least four brakes, wherein said axels comprises at least two hydrostatic steerable hub reduction axles with a first one on a front and a second one on a rear of said vehicle and configured said vehicle mobility, wherein said rear axle houses a hydrostatic motor and a drop box, with a drive from said rear to front axle is transmitted via a propeller shaft, wherein said axles are configured to be steered with a plurality of configurations and said vehicle is configured to be driven in both directions at a same speed; a mixing drum is disposed over said chassis on said rear end of said vehicle behind said housing and said operator cabin, wherein said drum comprises an agitator spiral blades arrangement which is configured to mix/agitate an amount of cement, sand, aggregates and water in appropriate proportions and said mixing drum is coupled to a hydrostatic pump and a motor with a suitable gear box configuration and operated from inside said operator cabin where a mixing speed of said drum is configured to be varied according to a desired requirement, wherein said configuration of said mixing drum is configured to be powered through a second engine, wherein said second engine from said pair of IC engines is configured to drive said mixing drum in order to perform said desired requirements and said first engine from said pair of IC engines is configured to propel said vehicle mobility and steering system.
Another embodiment of the invention states that said mixer further comprises a loading arm and a bucket operated through a hydraulic pump coupled to said second engine via hydraulic cylinders and mechanical links and disposed on rear end of said vehicle, wherein said loading arm and said bucket is configured to collect and feed said cement, sand, and aggregate in appropriate proportions from a specific location into said mixing drum, wherein said arm and bucket is configured to be operated from said engine via a pump an at least two hydraulic cylinders which are attached to said vehicle. The loading arm and bucket is coupled to a weighing system which consists of a plurality of weight sensors, wherein said weighing system is operatively coupled to said operator cabin control modes in order to notify an operator a quantity of sand, cement and aggregates being fed to said mixing drum via said loading arm and bucket.
Another embodiment is that at least two water tanks are disposed on a left and right side of said vehicle and operational through second engine of said vehicle, wherein said at least two water tanks are configured to transfer a required amount of water into said mixing drum, wherein said water tanks are provided with hose connections to transfer a flow of water via a water pump, wherein a flow meter is coupled to said water tanks and operator cabin in order to notify operator an amount of water being fed to said mixing drum.
Another embodiment of the present invention states a method of operating a twin-engine self-loading concrete mixer. The method comprising steps: activating a first engine from a pair of IC engines enclosed within a housing which is disposed over a chassis of a vehicle, in order to propel vehicle movement and steering operations via a plurality of hydraulic pumps, wherein said IC engines are configured to be operated in an operator cabin which is placed besides said housing over said chassis of said vehicle; activating a second engine from said pair of IC engines with said operator cabin having a plurality of control modes, wherein said second engine is configured to actuate the mixing drum operations via a hydraulic pump; actuating a loading arm and a bucket operated through a hydraulic pump coupled to said second engine via said control modes in order to collect an appropriate proportion of cement, sand and aggregates, wherein said collection is configured to be weighed by a weighing system coupled to said loading arm and operatively coupled to said operator cabin; feeding said collected mixture to said mixing drum via an inlet provided at rear end of said drum from a rear end of said vehicle; agitating said mixture by adding a required amount of water from at least two water tanks disposed at a left and right side of said vehicle, via a hose connection and a water pump and with a flow meter to indicate an amount of water being fed to said drum, wherein said agitation is performed by an agitator disposed with said mixing drum; and rotating said mixing drum in both clockwise and counterclockwise directions through said second engine, wherein when said drum is rotated clockwise, said drum is configured to discharge an agitated concrete mixture of said cement: sand: aggregates: water in a specific direction via an outlet, wherein when said drum is rotated counterclockwise, said drum is configured to agitate/mix said mixture.
To further clarify advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings
BRIEF DESCRIPTION OF FIGURES
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
Figure 1 illustrates a block diagram of components installed in a twin-engine self-loading concrete mixer.
Figure 2 illustrates a flowchart of steps involved in operating said twin-engine self-loading concrete mixer.
Figure 3 illustrates a power transmission of a first engine and a second engine of said twin-engine self-loading concrete mixer.
Figure 4 illustrates a configuration of twin-engine over said vehicle chassis in accordance with an embodiment of the present invention.
Figure 5 illustrates an isometric view of the components of said twin-engine self-loading concrete mixer.
Figure 6 illustrates an isometric view of the components without housing/bonnet of said twin-engine self-loading concrete mixer.
Figure 7 illustrates hydraulic pumps coupled to said two engines of said twin-engine self-loading concrete mixer.
Figure 8 illustrates a side view of the vehicle loaded with said twin-engine self-loading concrete mixer.
Figure 9a-b illustrates a front view of said vehicle with and without bonnet/housing enclosing said twin-engines.
Figure 10 illustrates a top view of the vehicle with said twin-engine self-loading concrete mixer.
Figure 11 illustrates a rear-top view of said twin-engine self-loading concrete mixer.
Figure 12a-b illustrates said twin-engine self-loading concrete mixer with 4x2 configurations and 4x4 configurations.
Figure 13 illustrates an isometric view of a front-end loading said twin-engine self-loading concrete mixer.
Figure 14 illustrates an isometric view of a second engine configuration with front-end loading of said twin-engine self-loading concrete mixer.
Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have been necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present invention. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.
DETAILED DESCRIPTION
For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not intended to be restrictive thereof.
Reference throughout this specification to “an aspect”, “another aspect” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in an embodiment”, “in another embodiment” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or sub-systems or elements or structures or components proceeded by "comprises...a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.
Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
Figure 1 illustrates a block diagram of components installed in a twin-engine self-loading concrete mixer. The twin-engine self-loading concrete mixer mainly includes a housing (102) which is disposed over a chassis (104) of a vehicle and configured to enclose at least a pair of IC engines (106, 108), wherein said housing (102) is fixed over said chassis (104) as protective enclosure for said engines (106, 108) mounted on said vehicle chassis, wherein said chassis/frame (104) comprises of a plurality of steel tubes welded together in a manner to hold an overall weight of said vehicle, wherein said housing (102) is configured to be detachably attached over said vehicle chassis (104) in order to perform maintenance and inspection necessary for said vehicle operation.
An operator cabin (112) is disposed over said chassis (104) of said vehicle besides said housing (102) and parallel to it, wherein said operator cabin (112) comprises an operator compartment (114) with a steering system (116) and a plurality of control modes (118) in order to mobilize said vehicle and perform intended functions, wherein said steering system (116) is configured to be powered through a first engine (106), wherein said operator compartment (114) is configured to perform a swivel function with at least 180 degrees swivel along a vertical axis with said compartment (114) when swivel in forward direction, said vehicle is configured to be driven on road and with said compartment (114) being in backward direction, said vehicle is configured to perform site operations.
An independent braking unit (120) is disposed within said operator cabin (112) and fixed over axles (124) for each wheel of said vehicle, wherein said braking unit (120) comprises at least four brakes (122) and is configured to provide a single pedal operation via a master cylinder from said cabin and thereby actuate said at least four brakes (122), wherein said axels (124) comprises at least two hydrostatic steerable hub reduction axles (126) with a first one on a front and a second one on a rear of said vehicle and configured said vehicle mobility, wherein said rear axle (126) houses a hydrostatic motor and a drop box, with a drive from said rear to front axle is transmitted via a propeller shaft, wherein said axles (124) are configured to be steered with a plurality of configurations and said vehicle is configured to be driven in both directions at a same speed.
A mixing drum (130) is disposed over said chassis (104) on said rear end of said vehicle behind said housing (102) and said operator cabin (112), wherein said drum (130) comprises an agitator spiral blades arrangement (132) which is configured to mix/agitate an amount of cement, sand, aggregates and water in appropriate proportions and said mixing drum (130) is coupled to a hydrostatic pump (134) and a motor (136) with gear box configuration (128) disposed within said housing (102) and operated from inside said operator cabin (112) where a mixing speed of said drum (130) is configured to be varied according to a desired requirement, wherein said configuration (128) of said mixing drum (130) is configured to be powered through a second engine (108), wherein said second engine (108) from said pair of IC engines is configured to drive said mixing drum (130) in order to perform said desired requirements and said first engine (106) from said pair of IC engines is configured to propel said vehicle mobility and said steering system (116).
The mixing drum (130) is configured to be rotated in both clockwise and counterclockwise directions through said second engine (108), wherein when said drum (130) is rotated clockwise, said drum (130) is configured to discharge an agitated concrete mixture of said cement: sand: aggregates: water in a specific direction via an outlet, wherein when said drum (130) is rotated counterclockwise, said drum is configured to agitate/mix said mixture.
The mixing drum (130) is configured to be raised via said hydrostatic pump (134) when a quick discharge is desired and said drum is configured to be raised and swiveled in left or right of said vehicle in order to discharge said mixture.
A loading arm and a bucket (138) operated through a hydraulic pump coupled to said second engine (108) via hydraulic cylinders and mechanical links and disposed on rear end of said vehicle, wherein said loading arm and said bucket (138) is configured to collect and feed said cement, sand, and aggregate in appropriate proportions from a specific location into said mixing drum (130), wherein said arm and bucket (138) is configured to be operated from said engine (108) via a pump an at least two hydraulic cylinders (140) which are attached to said vehicle.
The loading arm and bucket (138) is coupled to a weighing system (142) which consists of a plurality of weight sensors, wherein said weighing system (142) is operatively coupled to said operator cabin (112) control modes (118) in order to notify an operator a quantity of sand, cement, aggregates and water being fed to said mixing drum via said loading arm and bucket (138).
The mixer further comprises at least two water tanks (144) are disposed on a left and right side of said vehicle and operational through second engine (108) of said vehicle, wherein said at least two water tanks (144) are configured to transfer a required amount of water into said mixing drum (130), wherein said water tanks (144) are provided with hose connections to transfer a flow of water via a water pump, wherein a flow meter is coupled to said water tanks (144) and operator cabin (112) in order to notify operator an amount of water being fed to said mixing drum (130).
Figure 2 illustrates a flowchart of steps involved in operating said twin-engine self-loading concrete mixer. The method of operating a twin-engine self-loading concrete mixer mainly includes following steps.
The step (202) involves activating a first engine from a pair of IC engines enclosed within a housing which is disposed over a chassis of a vehicle, in order to propel vehicle movement and steering operations via a plurality of hydraulic pumps, wherein said IC engines are configured to be operated in an operator cabin which is placed besides said housing over said chassis of said vehicle. The step (204) involves activating a second engine from said pair of IC engines with said operator cabin having a plurality of control modes, wherein said second engine is configured to actuate the mixing drum operations via a hydraulic pump.
The further step (206) involves actuating a loading arm and a bucket operated through a hydraulic pump coupled to said second engine via said control modes in order to collect an appropriate proportion of cement, sand and aggregates, wherein said collection is configured to be weighed by a weighing system coupled to said loading arm and operatively coupled to said operator cabin;
The step (208) involves feeding said collected mixture to said mixing drum via an inlet provided at rear end of said drum from a rear end of said vehicle. The step (210) involves agitating said mixture by adding a required amount of water from at least two water tank disposed at a left and right side of said vehicle, via a hose connection and a water pump and with a flow meter to indicate an amount of water being fed to said drum, wherein said agitation is performed by an agitator disposed with said mixing drum.
The final step (212) involves discharging an agitated concrete mixture of said cement, sand aggregates, water in a specific direction via an outlet, wherein when said drum is rotated counterclockwise, said drum is configured to discharge said agitated concrete mixture agitate/mix said mixture.
Figure 3 illustrates a power transmission of a first engine and a second engine of said twin-engine self-loading concrete mixer. The twin-engine of said self-loading concrete mixer (SLCMS) have different configurations and power transmission. The first engine (Engine 1) is configured to drive and/or propel the vehicle from one location to another location and performs steering functions in order to mobilize the vehicle/mixer from place to place. The power from the first engine is transmitted to two hydraulic pumps, with one the vehicle movement is propelled and with second one steering operation is performed. The power here is driven further to two hydraulic motors for each vehicular mobilization and steering operation. The engine one is further coupled to a two-speed gearbox via a pump and motor which is integrated with rear axle of the vehicle and here the front wheels are driven via a propeller shaft. Further, the engine one is coupled to hydraulic cylinders via pump and motor to perform steering operation.
The second engine (Engine 2) is configured to perform the concrete collecting, feeding and discharging operations of the concrete mixer. The power transmission from engine 2 goes here as, from two hydraulic pumps to perform drum operations which can be agitating, charging and discharging of the concrete mixture, from the first pump and in regard to second pump, loading arm, water pump operation and auxiliary functions are implemented herein.
The first pump of second engine is coupled to a hydraulic motor which drives or rotates the mixing drum via a gear box provided inside the operator cabin. In an embodiment, a first pump of second engine is provided for rotating operation of the mixing drum and a second pump is configured for performing swiveling/ lifting and loading arm operations of the mixing drum. When the vehicle is ready to discharge the concrete and is in static condition,, the first engine is turned in off condition, therefore the steering functions and other vehicular movement is ceased which reduces the consumption of fuel and thereby enhances the life of vehicle components. Then the second engine is turned on in order to perform preparing of concrete. Both the engines provided herein can have different configurations in order to maintain load balance of the vehicle and these engines (generally internal combustions) can be of small capacity than a single engine provided in conventional SLCMs.
The all-wheel steering, all-wheel drive vehicle can also be propelled with a mechanical transmission in manual, automatic and automated manual (AMT) versions with front & rear end loading configurations and with drum sizes varying from 1m3 to 6m3.
Figure 4 illustrates a configuration of twin-engine over said vehicle chassis in accordance with an embodiment of the present invention. The front view is displayed with an operator cabin (402) and a first engine (406) and a second engine (410). Different configurations of the engines can be assembled over chassis of vehicle as here the first engine (406) is placed over the front and the second engine (410) is placed/assembled behind the first engine. Some other configurations are possible which are described later. The first engine (406) herein is provided with an air intake system (404) and a water-cooling system (408) and the second engine (410) is coupled with an air intake system (414) and a water-cooling/engine cooling system (412).
Figure 5 illustrates an isometric view of the components of said twin-engine self-loading concrete mixer. The self-loading concrete mixer with a twin-engine is displayed. The mixer is mounted over a chassis of a vehicle and consists of a front and rear end. The front end of the vehicle is provided with a cabin (502) where all controls of the mixer can be operated in different configuration such as manual, or automatic or automatic manual transmission (AMT). The cabin is provided with a comparting or operating compartment which can be swiveled in 180 degrees such that while driving on the road an operator is swiveled forward and while performing concrete making, said operator is swiveled backwards.
The cabin controls are coupled to twin-engines which are enclosed inside a housing or bonnet (504) in which two engines of less horse power than the conventional single engine of SLCMs is assembled. A first one is provided for vehicular movement and steering operations of the vehicle and the second one is provided for preparing concrete mixture. The actuation of first and second engine is provided from the operating cabin (502). When the vehicle is driven on wheels along the road engine one is actuated or turned on and second engine is kept off. During the preparation of the concrete mixture, the second engine starts rotating a mixing or agitating drum (510) which is mounted below the bonnet (504) and cabin (502) via hydraulic pumps.
A loading arm (512) is rotatably coupled to frame of the SLCM and to said second engine via hydraulic pump and cylinders and said arm (512) is coupled with a bucket (514). The operating controls from the cabin (502) are provided to said arm (512) and said bucket (514) to lower the bucket (514) and collect sand, cement and aggregates in desired proportions and feed it to the drum (510). A water tank or at least two water tanks (516) are provided on the left and right side of the vehicle. The water is fed to the drum (510) via a hose connection by a water pump and a flow meter is provided in order that the operator gets notified that how much quantity is required and is being driven from the tanks (516) to the drum (510).
At least two hydrostatic steerable hub reduction axles (506) are provided and with a first one on a front and a second one on a rear of said vehicle and configured said vehicle mobility, wherein said rear axle (506) houses a hydrostatic motor and a drop box, with a drive from said rear to front axle is transmitted via a propeller shaft, wherein said axles (506) are configured to be steered with a plurality of configurations and said vehicle is configured to be driven in both directions at a same speed. Two exhaust pipes (508) are provided on the front of the vehicle. These exhaust nozzles (508) can be placed at any other location possible depending upon the configuration of the engines.
Figure 6 illustrates an isometric view of the components without housing/bonnet of said twin-engine self-loading concrete mixer. The placement of air intake system of the twin-engine depends upon the configuration of the engines. As shown the first engine has water cooling system in front of the vehicle along the windward direction and the second engine has the cooling system normal to the first engine cooling system and is placed besides the operator cabin. The configuration has dual exhaust nozzles in front of the vehicle and is placed normal to the windward direction of the vehicle.
Figure 7 illustrates hydraulic pumps coupled to said two engines of said twin-engine self-loading concrete mixer. The twin engine includes two four hydraulic pumps (702) with first and second one configured for movement of vehicle and steering operation and the third and fourth one housed on second engine for the drum and loading arm operations of the mixer. The first and second pumps (702) are coupled to the first engine and the second and third pumps (702) are coupled to the second engine.
Figure 8 illustrates a side view of the vehicle loaded with said twin-engine self-loading concrete mixer. The operator cabin has mainly two control modes in the operating compartment with the first mode when the compartment is swiveled forward in order to mobilize vehicle and perform steering operations, from place to place and the second control mode is when the compartment is swiveled backwards in order to perform drum or mixing operations of concrete. The mixing drum can be swiveled clockwise and counterclockwise and can be raised and lowered in order to discharge the concrete slurry. The loading arm can be lowered along with the bucket attached to it in order to collect the material from the ground level and then raised to feed said material into the mixing drum. The operator cabin with control modes activates first and second engines according to the desired operations of the vehicle.
Figure 9a-b illustrates a front view of said vehicle with and without bonnet/housing enclosing said twin-engines. As displayed, the self-loading concrete mixer (SLCM) with bonnet or housing at the front which is configured to enclose two engines of lower capacity along with the air intake and water cooling system and the hydraulic pumps coupled therewith.
Figure 10 illustrates a top view of the vehicle with said twin-engine self-loading concrete mixer. Here the engine configuration is displayed with the first engine for vehicular movement is assembled at the front and the second engine for drum operations is assembled perpendicular to the first engine. The mixing drum is placed at the rear end of the vehicle and is coupled with the loading arm and bucket to feed the material inside the drum for agitation. The drum is operated from the cabin.
Figure 11 illustrates a rear-top view of said twin-engine self-loading concrete mixer. Here the rear top view of the SLCM is displayed. The capacity of the drum can be varied according the requirement of the construction and the volume of associated bucket with weighing system can also be varied.
Figure 12a-b illustrates said twin-engine self-loading concrete mixer with 4x2 configurations and 4x4 configurations. The 4x2 configuration states that the only the rear two wheels are provided torque by the first engine via the axle hub while the front two wheels are provided only to bear the load (a dead axle). This enhances the reduction of power, however, for 4x4 configurations all the four wheels are provided with the torque via axles in order to drive the vehicle.
Figure 13 illustrates an isometric view of a front-end loading said twin-engine self-loading concrete mixer. The front-end loading of the vehicle is displayed. Here, the operator cabin and the twin engine configuration enclosed with the housing/bonnet are assembled over the front and the rear axles of the chassis of the vehicle. The cabin is mounted over the right or left front wheel in order to provide a clear view while mobilizing the vehicle and the housing/bonnet of twin-engine configuration is placed over the right or left rear wheel of the vehicle behind the cabin. The drum operations are assembled from the left or right front wheel to left or right rear wheel of the chassis of vehicle. The configuration can be provided in both 4x2 and 4x4 configurations.
Figure 14 illustrates an isometric view of a second engine configuration with front-end loading of said twin-engine self-loading concrete mixer. As mentioned earlier that different configurations are possible for the placement of the twin engines, such as herein with the front-end loading vehicle, the twin engine configuration which is placed over the rear axle of the vehicle. The first and the second engines are placed parallel to each other with their water -cooling system facing the sideward of the vehicle and thereby the air intake system. The exhaust nozzles for each engine can be placed perpendicular to the horizontal plane of the vehicle.
In this invention, since two engines are used, the hydraulic pumps used for vehicle mobility and steering operation alone are fitted on one engine. And the other engine houses the hydraulic pumps for mixing drum and implements pump operations. For the ease of explanation, the engine 1 is configured for mobility and steering operations and engine 2 is configured for drum and to implement pump operations. During empty travel after unloading/discharging concrete or travelling empty from one place to another, the engine 1 housing the travel & steering pumps will only be operational and the engine 2 is kept off.
Similarly, during stationary operations such as long hours of concrete discharge and at the time of filling cement and water, the engine 1 is kept off & engine 2 will be operational. This saves enormous amount of fuel & operational cost. During loading operation & transporting mode (transporting concrete), both engine 1 & 2 will be functional.
The twin engine configuration has many advantages over convention SLCMs, such as, there is a need-based operation or operation specific engine selection is possible in twin engine SLCM concept. Few advantages are: Better fuel efficiency, lesser operational cost, easy maintenance lesser vehicle cost, less wear & tear and higher life for hydraulic pumps & associated parts in case of a twin engine concept. The heat produced by churning oil unnecessarily is low. Lesser vibration and noise compared with large size conventional IC engines for most of the time.
In twin engine concept, during break down of one engine, the second engine will be operational to safeguard the vehicle. When the vehicle operated with single engine fails, the mobility of the vehicle is completely lost & drum agitation will be stopped, this will lead to settling of concrete in the drum which calls for expensive repair for the drum & loss of concrete & time. But in case of two engine vehicle configuration, if the mobility engine break downs, other engine will be functional & safeguard the drum from concrete settling & if the drum agitation/mixing engine fails, mobility engine will be functional & vehicle can be moved to discharge zone & discharge can be done through the man holes provided on the drum.
As the pumps are divided and coupled on two engines, simple mechanical engine solutions can be derived. Mechanical engines are known for its simplicity, easy repair, cheap maintenance/service cost than high end electronic engines. Due to its compact size, engines can be placed anywhere on the vehicle chassis to achieve better weight distribution. If a mechanical drive is used, engine can be placed similar like conventional driveline & other engine can be positioned anywhere on the chassis.
The present invention further states that various configurations of SLCMs where twin engine concept can be applied. The drive configurations include Hydrostatic drive configuration; Mechanical drive this includes manual, automatic & automated manual transmissions; Combination of hydrostatic & mechanical drive configuration with electronic engines. In twin engine configuration, one engine can be with ECU controlled engine & other with mechanical or both with mechanical engines or both with ECU controlled engines.
There can be front end loading type as mentioned in figure 14 and can be rear end loading type. Also, this concept can be applied on SLCMs of various capacity drum sizes ranging from 1m3 to 6m3.
The twin-engine self-loading concrete mixer also includes an electrical system with a suitable battery disposed within said operator cabin and is configured to start said vehicle and turn on lighting and said control modes in order to perform desired actions.
The first engine from said pair of IC engines is configured to drive at least two hydraulic pumps (preferably four) with first and second hydraulic pump are configured for vehicle mobility and steering operation with a two-speed gear box integrated with said rear axle of vehicle via a first hydraulic motor in order to drive wheels of vehicle via a propeller shaft, wherein third and fourth second hydraulic pump are configured for the drum and loading arm operations of the mixer.
The second engine from said pair of IC engines is configured to drive four two hydraulic pumps, with first and second one configured for movement of vehicle and steering operation and the third and fourth one housed on second engine for the drum and loading arm operations of the mixer. The first and second pumps are coupled to the first engine and the second and third pumps are coupled to the second engine.
The steering operations and wheel drive of said vehicle is configured to be propelled with a mechanical transmission in manual or automatic and/or automated manual (AMT) modes having front and rear end loading configurations.
The mixing drum size is configured to vary from 1 cubic meter to 6 cubic meters.
The functions of various components in SLCM can be explained as below:
Mixing drum: It is the key component of the machine & is meant for agitating the concrete mix i.e., cement, sand, aggregates (fragmented stones) and water. Mixing drum is powered by a hydrostatic pump, motor & gearbox configuration. The drum mixing speed can be varied & can be selected accordingly to the requirement or operator discretion. The mixing drum can be rotated in both clockwise & anti clockwise directions, clockwise rotation is for discharging & anti clockwise is for mixing (when viewed from vehicle rear end). The drum can be raised and discharged when quick discharge is required; also same can be raised and swiveled for discharge. The mixing drum unit is attached to the vehicle frame.
Loading Arm & Bucket: This unit is intended for the collection & feeding of various materials to mixing drum for the preparation of concrete mix. It is operated by a pump & two hydraulic cylinders (preferably four) and is attached to the vehicle frame. A weighing system is also attached to the same, this will notify the operator, the quantity/weight of the material which is fed to the drum. Various linkage mechanisms & cylinders are associated with this system to perform the above-mentioned function.
Water tank: The vehicle is equipped with two water tanks on both sides, hose connections are provided to transfer water to mixing drum via water pump, a flow meter is also fitted in this system to notify the operator the quantity of water fed to the drum.
Cabin: The vehicle is fitted with a cabin to house one operator, the cabin consists of an operator compartment, steering system & various other controls for the vehicle mobility and to perform the intended functions. The operator compartment is swivel type, 180-degree swivel in vertical axis, swiveled in vehicle forward direction is meant for on-road driving and swiveled to vehicle backward direction is meant for working phase or to perform concrete batching /site operation
Bonnet/housing: Incorporated with a bonnet to cover the twin engines, water cooling systems, air intake systems, hydraulic tank, associated hydraulic pumps etc. This can be lifted & held to do any repair work/ inspection. Besides this, it provides noise & heat insulation to the operator.
Chassis/Frame: It is the foundation structure/load bearing element which supports all the components fitted on the vehicle, same is made of steel tubes, welded each other in such a way that it can house all the components.
Brakes: Independent braking unit is provided on axles for each wheel, single pedal operation via master cylinder from cabin will actuate all four brakes. Parking brake is also configured in one axle.
Axles: Two number hydrostatic steerable hub reduction axles one on front & other on rear are used for vehicle mobility. Rear axle houses the hydrostatic motor & drop box, drive from rear to front axle is transmitted via propeller shaft. This entire drive configuration makes the machine as an all-wheel drive vehicle. As both axles are steerable, various steering configurations such as four-wheel steering, two-wheel steering & crab steering are provided. And the vehicle can be driven in both directions at same speed.
Tyres: Four number off-highway mining tyres are fitted on both axles, same can be used with & without tube options.
Electrical System: 12V electric system with suitable battery is used for starting, lighting & for enabling other operations, all lamps, warning & visual display systems are configured as per the legal requirement.
The present invention relates to the usage of two IC engines for self-loading concrete mixer (SLCM) application for better fuel efficiency, lower emissions, lesser NVH, longer life of components & for overall cost advantage. The conventional self-loading concrete mixers (SLCM) use heavy large displacement single IC engine for various operations which has many disadvantages. For example, all the hydraulic pumps of SLCM are coupled to single IC engine, however when the SLCM is moved from one pace to another after completion of work or travel return after discharge of concrete, the travel pump coupled to engine alone is required & employed & other pumps are also functional since the same is connected in series with engine which is unneeded.
Furthermore, all the hydraulic pumps (for accessory operations) are operational which heats up the oil unnecessarily and increase the fuel consumption & reduce the pumps life & associated parts life. Also, the cost of large displacement single IC engine is more than two lesser displacement small IC engines. Nowadays large displacement IC engines uses electronic injection systems which require expensive maintenance & skilled labor for service/repair which increases the overall cost of vehicle. Some of the Key advantages of using twin engines (2 engines) in SLCM application are listed below:
The need-based operation/ operation specific engine configuration is possible in twin engine SLCM concept. For example, vehicle mobility is independently performed by travel pump & motor configuration which is coupled with a gear box, propeller shaft, axle unit and tyres. All other functions simultaneously work at many instances. Total power demand for various operations is calculated & power configuration is done for individual pumps. Maximum power required is for mobility (for travelling with load), here derive independent engine for mobility function. Also steering pump will be coupled with this engine.
The other operations such as drum operation for agitation/mixing, water pump & loading arm & bucket operation pumps can be coupled with the other engine. And the same can be turned off & on based on the requirement such as while travelling for long distance from one place to another, travelling return empty after discharge etc. This will save enormous amount of fuel, reduces vibrations & noise. Besides this, the engine coupled with travel pump can be turned off during long hours of discharge & mixing periods.
The wear & tear of hydraulic pumps & associated parts will be drastically reduced in case of a twin engine concept. Whereas in case of a single engine configuration, since all hydraulic pumps are coupled with same engine, all will be functional & will be pumping oil to tank consuming power & generating heat, this will reduce the components life.
In twin engine concept, during break down of one engine, the second engine will be operational to safeguard the vehicle. When the vehicle operated with single engine fails, the mobility of the vehicle is completely lost & drum agitation will be stopped, this will lead to settling of concrete in the drum which calls for expensive repair for the drum & loss of concrete & time. But in case of two engine vehicle configuration, if the mobility engine break downs, other engine will be functional & safeguard the drum from concrete settling & if the drum agitation/mixing engine fails, mobility engine will be functional & vehicle can be moved to discharge zone & discharge can be done through the man holes provided on the drum.
As the pumps are divided & coupled on two engines, simple mechanical engine solutions can be derived. Mechanical engines are known for its simplicity, easy repair, cheap maintenance/service cost than high end electronic engines.
Due to its compact size, twin engine can be placed anywhere on the vehicle chassis to achieve better weight distribution & from service point of view
If a mechanical drive is used, one engine can be placed similar to conventional driveline systems and the other engine can be positioned anywhere on the chassis.
The SLCMs are categorized based on their drum capacity ranging from 1m3 to 6m3.Various types of SLCMs which are in production now are front end loading & rear end loading types.
The drawings and the forgoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, orders of processes described herein may be changed and are not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts necessarily need to be performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples. Numerous variations, whether explicitly given in the specification or not, such as differences in structure, dimension, and use of material, are possible. The scope of embodiments is at least as broad as given by the following claims.
Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any component(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature or component of any or all the claims.
,CLAIMS:1. A twin-engine self-loading concrete mixer comprising:
a housing (102) disposed over a chassis (104) of a vehicle and configured to enclose at least a pair of IC engines (106, 108) coupled to each other through a drive (110), wherein said housing (102) is fixed over said chassis (104) as a protective enclosure for said engines (106, 108) mounted on said vehicle chassis, wherein said chassis/frame (104) comprises of a plurality of steel tubes welded together in a manner to hold an overall weight of said vehicle, wherein said housing (102) is configured to be detachably attached over said vehicle chassis (104) in order to perform maintenance and inspection necessary for said vehicle operation;
an operator cabin (112) disposed over said chassis (104) of said vehicle besides said housing (102) and parallel to it, wherein said operator cabin (112) comprises an operator compartment (114) with a steering system (116) and a plurality of control modes (118) in order to mobilize said vehicle and perform intended functions, wherein said steering system (116) is configured to be powered through a first engine (106), wherein said operator compartment (114) is configured to perform a swivel function with at least 180 degrees swivel along a vertical axis with said compartment (114) when swivel in forward direction, said vehicle is configured to be driven on road and with said compartment (114) being in backward direction, said vehicle is configured to perform site operations;
an independent braking unit (120) disposed within said operator cabin (112) and fixed over axles (124) for each wheel of said vehicle, wherein said braking unit (120) comprises at least four brakes (122) and is configured to provide a single pedal operation via a master cylinder from said cabin and thereby actuate said at least four brakes (122), wherein said axels (124) comprises at least two hydrostatic steerable hub reduction axles (126) with a first one on a front and a second one on a rear of said vehicle and configured said vehicle mobility, wherein said rear axle (126) houses a hydrostatic motor and a drop box, with a drive from said rear to front axle is transmitted via a propeller shaft, wherein said axles (124) are configured to be steered with a plurality of configurations and said vehicle is configured to be driven in both directions at a same speed;
a mixing drum (130) is disposed over said chassis (104) on said rear end of said vehicle behind said housing (102) and said operator cabin (112), wherein said drum (130) comprises an agitator spiral blades arrangement (132) which is configured to mix/agitate an amount of cement, sand, aggregates and water in appropriate proportions and said mixing drum (130) is coupled to a hydrostatic pump (134) and a motor (136) with gear box configuration (128) disposed within said housing (102) and operated from inside said operator cabin (112) where a mixing speed of said drum (130) is configured to be varied according to a desired requirement, wherein said configuration (128) of said mixing drum (130) is configured to be powered through a second engine (108), wherein said second engine (108) from said pair of IC engines is configured to drive said mixing drum (130) in order to perform said desired requirements and said first engine (106) from said pair of IC engines is configured to propel said vehicle mobility and said steering system (116).

2. The twin-engine self-loading concrete mixer as claimed in claim 1, wherein said mixing drum (130) is configured to be rotated in both clockwise and counterclockwise directions through said second engine (108), wherein when said drum (130) is rotated clockwise, said drum (130) is configured to discharge an agitated concrete mixture of said cement: sand: aggregates: water in a specific direction via an outlet, wherein when said drum (130) is rotated counterclockwise, said drum is configured to agitate/mix said mixture.

3. The twin-engine self-loading concrete mixer as claimed in claim 1, wherein said mixing drum (130) is configured to be raised via said hydrostatic pump (134) when a quick discharge is desired and said drum is configured to be raised and swiveled in left or right of said vehicle in order to discharge said mixture.

4. The twin-engine self-loading concrete mixer as claimed in claim 1, wherein said mixer further comprises:
a loading arm and a bucket (138) operated through a hydraulic pump coupled to said second engine (108) via hydraulic cylinders and mechanical links and disposed on rear end of said vehicle, wherein said loading arm and said bucket (138) is configured to collect and feed said cement, sand, and aggregate in appropriate proportions from a specific location into said mixing drum (130), wherein said arm and bucket (138) is configured to be operated from said engine (108) via a pump an at least two hydraulic cylinders (140) which are attached to said vehicle.

5. The twin-engine self-loading concrete mixer as claimed in claim 4, wherein said loading arm and bucket (138) is coupled to a weighing system (142) which consists of a plurality of weight sensors, wherein said weighing system (142) is operatively coupled to said operator cabin (112) control modes (118) in order to notify an operator a quantity of sand, cement and aggregates being fed to said mixing drum via said loading arm and bucket (138).

6. The twin-engine self-loading concrete mixer as claimed in claim 1, wherein said mixer further comprises:
at least two water tanks (144) disposed on a left and right side of said vehicle and operational through second engine (108) of said vehicle, wherein said at least two water tanks (144) are configured to transfer a required amount of water into said mixing drum (130), wherein said water tanks (144) are provided with hose connections to transfer a flow of water via a water pump, wherein a flow meter is coupled to said water tanks (144) and operator cabin (112) in order to notify operator an amount of water being fed to said mixing drum (130), and
wherein said mixed further comprises:
an electrical system with a suitable battery disposed within said operator cabin and is configured to start said vehicle and turn on lighting and said control modes in order to perform desired actions.

7. The twin-engine self-loading concrete mixer as claimed in claim 1, wherein said first engine from said pair of IC engines is configured to drive at least two hydraulic pumps with first hydraulic pump configured for vehicle mobility with a two-speed gear box integrated with said rear axle of vehicle via a first hydraulic motor in order to drive wheels of vehicle via a propeller shaft, wherein second hydraulic pump is configured for steering operation of said vehicle with a plurality of hydraulic cylinders for steering operations via a second hydraulic motor.

8. The twin-engine self-loading concrete mixer as claimed in claim 1, wherein said second engine from said pair of IC engines is configured to drive at least two hydraulic pumps, with a first pump for said mixing drum operations and a second pump for implementing loading arm, water pump operation and auxiliary functions, wherein first hydraulic pump of said second engine is configured to drive a hydraulic motor with a drive to drum via said gear box, and wherein said steering operations and wheel drive of said vehicle is configured to be propelled with a mechanical transmission in manual or automatic and/or automated manual (AMT) modes having front and rear end loading configurations.

9. The twin-engine self-loading concrete mixer as claimed in claim 1, wherein said mixing drum size is configured to vary from 1 cubic meter to 6 cubic meters, and
wherein said first and second IC engines are operatively coupled to each other via said drive (110), in order to propel said operations of said mixer, wherein when said first engine fails while operations said second engine is configured to drive loads associated with said first engine and vice-versa.

10. A method of operating a twin-engine self-loading concrete mixer, the method comprising steps:
activating a first engine from a pair of IC engines enclosed within a housing which is disposed over a chassis of a vehicle as protective enclosure for said engines mounted on said vehicle chassis, wherein said IC engines are configured to be operated in an operator cabin which is placed besides said housing over said chassis of said vehicle;
activating a second engine from said pair of IC engines with said operator cabin having a plurality of control modes, wherein said second engine is configured to actuate the mixing drum operations via a hydraulic pump;
actuating a loading arm and a bucket operated through a hydraulic pump coupled to said second engine via said control modes in order to collect an appropriate proportion of cement, sand and aggregates, wherein said collection is configured to be weighed by a weighing system coupled to said loading arm and operatively coupled to said operator cabin;
feeding said collected mixture to said mixing drum via an inlet provided at rear end of said drum from a rear end of said vehicle;
agitating said mixture by adding a required amount of water from at least two water tanks disposed at a left and right side of said vehicle, via a hose connection and a water pump and with a flow meter to indicate an amount of water being fed to said drum, wherein said agitation is performed by an agitator spiral blades arrangement disposed with said mixing drum; and
discharging an agitated concrete mixture of said cement, sand aggregates, water in a specific direction via an outlet, wherein when said drum is rotated counterclockwise, said drum is configured to discharge said agitated concrete mixture agitate/mix said mixture.