FR2561709A1 - Cooling system for utility vehicle - Google Patents

Abstract

A coolant radiator (88) and an oil cooler heat exchanger (64) are mounted one over the other, over an engine (42). They are cooled by an airstream pulled through the engine compartment by a single blower (50) low down in the engine compartment. Ducts (52) guide the airflow to the radiators, and flexible hoses connect the water and oil circuits to the radiators. The two radiators are mounted in separate support frames and have pivots one above the other. Stays secure the raised position while catches secure the dropped position.

Description

 The present invention relates generally to a cooling circuit comprising a liftable radiator and oil cooler assembly.

The invention relates more particularly to a cooling assembly for a loader with non-steerable wheels with sliding direction comprising two air / liquid heat exchangers, one for the engine coolant and the other for the hydraulic fluid, articulated separately to the - above the engine to facilitate cleaning, maintenance and the like.

 A non-steerable wheel loader is a compact, highly manoeuvrable vehicle in which the wheels on two opposite sides are driven independently.

The maneuver is effected by driving the wheels on opposite sides of the vehicle at different speeds and / or in different directions, usually by means of hydrostatic transmissions, to provide propulsion and steering. The driver is seated in front of the engine and between two hydraulically actuated loading arms, on which a bucket, fork, conveyor screw or other accessory can be mounted. Appropriate controls are provided in the driver's compartment for order the vehicle and the loading arms as well as the motorized accessory possibly mounted on the loader. In order to obtain efficient steering by sliding, these vehicles must necessarily have a relatively small wheelbase and track, and the maneuverability is further improved by an appropriate weight ratio between the front and rear axles in the loaded and unloaded state. Skid steer loaders should therefore be designed to provide compactness and the desired weight ratio between 1 front axle and the rear axle in order to facilitate sliding steering and handling of loads.

It is desirable to distribute the weight among the axles of skid steer loaders in such a way that. most of the weight is supported by the rear axle when the loader is empty or unloaded, and an appropriate balance is maintained when the vehicle is loaded. This in turn implies that the engine and its auxiliaries, which represent a significant part of the weight, are mounted behind the rear axle and in relatively close proximity to this axle. In addition, it is desirable to place these components as low as possible in order to lower the center of gravity and thereby improve the stability of the vehicle. Some skid steer loaders include air-cooled motors but most use liquid-cooled engines, whose cooling circuits are also among these study parameters0
In the past, a widely used solution for the calculation of cooling circuits for skid steer loaders consisted in placing the cooling circuit behind the engine, in the longitudinal alignment thereof. That is to say that the fan, the radiator and the oil cooler are aligned in a "stack" behind the engine. However, this arrangement is relatively bulky and thus harms the general compactness of the vehicle and it also engine accessibility for servicing, maintenance and equivalent operations.

 Cooling circuits of a more compact design have therefore been developed, but these prior solutions were not without drawbacks. For example, the Hydra-Mac skid steer loaders include radiators mounted on doors on the rear of the body. U.S. Patent 3,828,952 discloses a slip-direction loader in which the radiator is placed above the engine, a pair of fans being provided between the radiator and a grille placed in the rear More recently, U.S. Patent No. 4,117,902 describes a cooling circuit for a skid steer loader in which air is drawn through a rear grille by a fan placed in front of the engine and then it is blown through an oil cooler and a radiator that surmounts the engine compartment. Although these last two arrangements provide greater longitudinal compactness, compared to the axial stacks of cooling devices of the prior art, none of these provisions is adapted to facilitate appropriate access to the engine and its auxiliaries for maintenance and equivalent operations or for f facilitate cleaning of the engine radiator and / or oil cooler. It will be easy to understand that skid steer loaders usually work in adverse conditions which, in turn, frequently involve more stringent servicing and maintenance requirements. Prior art cooling systems severely limit access to the engine and its auxiliaries and they require at least a partial disassembly for access to the radiator or the oil cooler and / or for the cleaning of these auxiliaries, which, in turn, is time consuming and expensive.

 There has therefore been a need for an improved cooling circuit for a sliding-direction loader which avoids the drawbacks associated with axial stacking arrangements while bringing the advantage of compactness as well as better accessibility to the engine, to the cooler. oil and to the radiator without requiring any disassembly.

 The subject of the present invention is a liftable oil radiator and cooler assembly for a sliding direction loader which overcomes the difficulties described above as well as others which are linked to the prior art. According to the invention, which represents an improvement compared to the device described in AmOrique's US patent No. 4,117,902, a cooling assembly is produced which is particularly well suited for use with skid steer loaders. The cooling assembly of this patent comprises a pair of air / liquid heat exchangers, one of which is a radiator for cooling the hydraulic fluid and whose wall is a radiator for cooling the cooling fluid. of the engine, which are arranged one above the other and slightly in front of the engine.

The heat exchangers are mounted on shelves which are articulated independently on the inner side of one of the uprights, around generally longitudinal axes, in order to be able to pivot between a raised position and a lowered position. The lower shelf, which preferably carries the oil cooler, is supported at its free end in the lowered position by a fitting provided on the inner side of the opposite upright.

The upper shelf, which preferably contains the radiator of the engine, rests on the upper face of the lower shelf in the lowered position and includes a latch by means of which qu * alle can be locked snugly in the lowered position. The latch handle is also suitable for retaining the upper shelf or the two shelves if they are connected by a removable link, in the raised position.The shelves can tilt independently to facilitate cleaning of the two sides of each of the two radiators they contain, as well as access to the engine and its auxiliaries, including the underlying fan and its fairing.

The invention will be better understood by referring to the detailed description which follows, made with reference to the appended drawings in which
Figure 1 is a side view of a skid steer loader which includes the improved cooling system including the liftable oil cooler and radiator assembly of the present invention;
Figure 2 is a top plan view on a large scale of the engine compartment, the upper grid being removed for clarity of the drawing
Figures 3 and 4 are enlarged rear elevation views of the engine compartment, showing the liftable oil cooler and radiator assembly according to the invention in the lowered and raised positions, respectively
Figures 5 and 6 are sectional views taken generally along lines 5-5 and 6-6> respectively, of Figure 2, in the direction of the arrows; and
Figure 7 is a sectional view, taken generally along lines 7-7 of Figure 3, in the direction of the arrows.

 Referring to the drawings, in which similar reference numbers designate similar or corresponding elements in all the views and, with particular reference to FIG. 1, there is shown a skid steer loader 10 fitted with the circuit improved cooling according to the invention.

The skid steer loader 10 includes a pair of front wheels 12 and a pair of rear wheels 14, one wheel of each pair shown alone, mounted with a relatively small footprint and track to facilitate sliding steering. The compartment 16 of the conductor, which comprises a cage 18 for protection against overturning and a seat 20, is placed between two lifting arms 22. The inner ends of the lifting arms are connected, at articulation points 24, to uprights 26 provided at the rear of the chassis 28 of the vehicle. Equipment 30 such as a bucket, is mounted, at articulation points 32 of which only one is shown, on the outer ends of the lifting arms 22. L raising and lowering of the lifting arms 22 are ensured by a pair of double-acting jacks 34, each of which is mounted between a hinge point 26 provided on each lifting arm and a culation part point 38 provided - on the corresponding amount 26. The tilting of the bucket 30 is controlled by a single double-acting cylinder 40 mounted between the bucket and a crosspiece (not shown) which extends between the lifting arms.

 The driver's compartment 16 includes appropriate controls for controlling the skid steer loader 10, the lifting arms 22 and the bucket 30. A motor 42 is housed in an engine compartment placed behind the driver's compartment 16 and between the uprights 26 A rear door 44 is provided to give access to the motor 42 and to the members associated with it. As will be explained more fully below, the skid steer loader 10 includes a cooling circuit which itself comprises a liftable oil cooler and radiator assembly which is intended to facilitate better access for the needs of maintenance, aaintenance, cleaning and equivalent operations.

 Reference will now be made to FIGS. 2 and 5. The compartment 46 of the engine of the sliding-direction loader 10 comprises the engine 42, the cooling circuit 48 and members associated therewith.

The engine 42 is a liquid-cooled internal combustion engine, of the gas powered type or the diesel type. Motor 42, mounted at the rear, collects a set of conventional tandem pumps (not shown) which includes variable displacement valves connected to the hydraulic drive motor of the hydrostatic transmissions provided to independently drive each
Wheel set 12 and 14.

 The cooling circuit 48 of the loader 10 comprises a fan 50 which is driven by the motor 42. The fan 50 is placed inside a fairing 52 which extends upwards between the motor 42 and a barrier partition -fire or cross 54 extending between the uprights 26. A fuel tank (not shown) is disposed in the cavity between the seat back 20 and the cross 54. the fairing 52 includes an inlet 56 and an outlet 58 The ambient air is sucked in, through louvers 59 formed in the - door 44 by the fan 50 which passes it over the motor 42 and enters the inlet 56, passing under the seat 20, and it is discharged. upwards through the fairing 52, again by the fan 50 and discharge through the outlet 58 after having swept a liftable oil cooler and radiator assembly 60 according to the invention.

As will be explained more fully below, the liftable radiator and oil cooler assembly 60 makes it possible to tilt the two radiators independently of one another to facilitate servicing, maintenance and cleaning without disconnecting or removing any of the components.

Referring now to FIGS. 2 to 7, it can be seen that the liftable radiator and oil cooler assembly 60 according to the invention is placed in a position which overcomes the engine 42, the assembly being placed above and generally in front of the engine. The assembly 60 comprises a lower shelf 62 having the general shape of a rectangular frame, for internally supporting an oil cooler 64. The periphery of the shelf 62 has a cross section roughly in
L to support the oil cooler 64 in this shelf, while letting air circulate through the oil cooler. The oil cooler 64 includes a substantially conventional air / liquid heat exchanger, intended to cool the fluid hydraulic used by the sliding direction loader 10 for the centering of the wheels 12 and 14 and for the actuation of the arms 22. The oil cooler 64 is of conventional construction, and it comprises a pair of manifolds 65 arranged on its two opposite sides, one of which is shown most clearly in FIG. 6, and to which fittings 66 and 68 are connected. Pipes 70 and 72 are connected, respectively, to fittings 66 and 68 to circulate the hydraulic fluid through the oil cooler 64 which is placed directly above the outlet 58 of the fan shroud 52 when the lower shelf 62 is in the lowered position.

 The lower shelf 62 can switch between a lowered position and a raised position, as shown in Figures 3 and 4. In particular, two lateral branches or extensions 74 are provided on one side of the shelf 62 to be connected to pivots 76 so as to be able to tilt around a generally longitudinal axis 78. As shown, an extension 74 and its respective pivot 76 are mounted on the cross member 54, while the other extension and its respective pivot are mounted on a fitting 80 which is intended to support the silencer 82. The fitting 80 is fixed to the inner face of an upright 26 and to an adjacent part of the rear face of the cross member 54. A fitting 84 is provided on the inner face of the opposite upright 26 to support the free end of the lower shelf 62 in the lowered position.

 The liftable radiator and oil cooler assembly 60 also includes an upper shelf 86 intended to support a second air / liquid heat exchanger 88. The upper shelf also has the shape of a substantially rectangular frame, with an L-shaped periphery, to support the radiator 88 while letting the air pass through it. In particular, the second heat exchanger 88 is intended for the function of cooling the liquid cooling fluid which circulates in the engine 42. The heat exchanger 88 is of a conventional construction, and comprises a pair of collectors 90 and 92 provided at opposite ends and provided with fittings to which pipes 94 and 96 are connected, respectively.

A removable plug 98 is provided on the manifold 90 to allow the level of the coolant to be supplemented. Like the lower shelf 62, the upper shelf 86 comprises a pair of branches or extensions 100 which are connected by pivots 102 to describe a rocking movement around an axis 104 substantially longitudinal. An extension 100 and its pivot are mounted on the cross member 54, while the other extension and its pivot are mounted on the fitting 80. It is therefore visible that the shelves 62 and 86 are superimposed and can tilt independently around separate axes 78 and 104 substantially longitudinal, which are offset from each other both vertically and laterally.

 A locking mechanism is provided on the upper shelf 86, mainly for fixing the upper shelf by a removable link in the lowered position applied against the lower shelf 62, and for retaining the upper shelf in a raised position. The locking mechanism comprises a rod 106 having the general shape of an L, which comprises a longitudinal part which extends through the openings made in the free end of the upper shelf 86 and which is fixed by a washer. and a split pin 108. A tab 110 is fixed to the longitudinal part of the rod 106 to cooperate with a slot 112; as best seen in Figure 6, a slot which is formed in the inner surface of the upright 26 adjacent.The side portion of the rod 106, which is longer, ends in a hook 114 which is intended to cooperate , either with a slot 116 formed in the rear extreme extension 100 of the upper shelf 86, or with an opening 118 formed in the adjacent upright 26.

 When the end 114 of the rod 106 is placed in the opening 116, the tab 110 is engaged with a notch 112 and the radiator and oil cooler assembly 60 is fixed in a lowered position immediately above the outlet 38 of the fan shroud 52, so that air can be blown through the oil cooler 64 and then through the radiator 88 before exiting upwards, towards a grid (not shown) for exiting from engine compartment 46.

When it is desired to raise the upper shelf 86, the lateral part of the rod 106 is flexed outside to release the end 114 from the opening 116, so that it can be raised, thereby releasing the tab. 110 so that the upper shelf 86 can be raised to a raised position as shown in Figure 4. The end 114 of the rod 106 can then be engaged with the opening 118 of the upright 26 to retain the upper shelf in a raised position. A handle 120 is preferably provided on the upper shelf 86 to facilitate lifting.

 It is therefore visible that the radiator and oil cooler assembly 60 comprises two separate air / liquid heat exchangers or radiators 64 and 88, which overcome the compartment 46 of the engine and which are supported independently so as to be able to describe a tilting movement around hinge axes 78 and 104. The radiators 64 and 88 are supported in frames or shelves 62 and 86 of generally rectangular shape and are positioned in superposed positions in the normal lowered position, in which the lower shelf * - lower rests on a fitting 84 and the upper shelf rests on the first, and is fixed in place by the latch 110. The upper radiator 88 can be detachably fixed in the raised position by means of the rod 106 and the opening 118 When the upper radiator 88 is thus placed in the raised position, the lower radiator 64 can also be raised and fixed by a removable link in the raised position, s if desired, by means of a hook 122 which can be engaged with the handle 120 or another suitable part of the upper shelf 86. In the arrangement shown, the hook 122 is articulated to the lower shelf 62 to be able to engage with the handle 120 of the upper shelf 86 or disengage from this socket.

 It therefore appears from the above that the subject of the present invention is an improved cooling circuit which comprises a new liftable oil cooler and radiator assembly, which has several advantages compared to the prior art. The invention described in this specification is particularly well suited for use with public works vehicles such as skid steer loaders, the engine compartment of which must meet the compactness conditions which are specific to these vehicles. invention comprises two separate radiators which can switch independently between a lowered position to facilitate access to each of the faces of each radiator, or of the set of two radiators, as well as access to the engine and to the members associated with this engine, for servicing, maintenance, cleaning and equivalent operations. The liftable oil cooler and radiator assembly and the connection pipes are arranged so that they do not require any disassembly. Other advantages will be obvious to those skilled in the art. Although certain embodiments of the invention have been illustrated by the accompanying drawings and described in the detailed description above, it goes without saying that the invention is not limited to the embodiments described and that it must be considered as covering variants, equivalent solutions, modifications and / or rearrangements of elements which remain within the scope of the invention.

Claims (11)

 1. Cooling circuit for a sliding direction loader, hydrostatic control, comprising a ventilated engine compartment which contains a motor placed between two uprights (26, 26) behind a compartment (16) of the driver, characterized in that 'It includes: a fan placed between the compartments of the engine and the driver; a fairing (52) which surrounds said fan (50) and extends substantially upwards, from an inlet (56) to an outlet (58); upper (88) and lower (64) radiators, superimposed on each other, which extend between the uprights (26, 26) and above the outlet (58) of said fan shroud (52) ; means (100, 102) which support said upper radiator (88) with articulation to allow it to move between a raised position and a lowered position; means (74, 76) which support the lower radiator (64) with articulation to enable it to switch between a raised position and a lowered position; and means (106, 110, 112) which fix at least said upper radiator in at least the lowered position by a removable link.  2. Cooling circuit according to claim 1, characterized in that said means (100, 102) serving to support said upper radiator t88) with possibility of tilting comprise: a generally rectangular frame having opposite ends; a pair of side extensions (100) attached to one end of the frame in longitudinally spaced positions; and means (102) which connect said extensions to one of said uprights (26) to allow it to tilt about a substantially longitudinal axis (104).  3. Cooling circuit according to claim 1, characterized in that said means (74, 76) which support said lower radiator (64) with the possibility of tilting, comprise: a generally rectangular frame having opposite ends a pair of extensions lateral (74) fixed to one end of said frame, in positions spaced apart longitudinally; means (76) which connect said extensions to one of said uprights (26) to allow it to tilt about a substantially longitudinal axis (78); and a flange (84) fixed to the opposite upright (26) for supporting said frame in the lowered position.  4. Cooling circuit according to claim 1, characterized in that said means serving to fix at least the upper radiator (883 in at least the position lowered by a removable link) comprises: a latch (110) mounted on said tilting support means of the upper radiator (88), said latch (110) being selectively engaging with a notch (112) formed in one - of said uprights (26); and a control rod (106) connected to said latch, said rod comprising a folded end which can move between a storage position in which it can be engaged in an opening (116) of said tilting support means of said upper radiator (88), and an extension position in which it can be engaged in an opening (118) formed in one of said uprights (26) for holding said upper radiator (88) in a raised position.  5. A cooling circuit as claimed in claim 1, characterized in that it comprises means (122) forming a hook intended to selectively connect said upper and lower tilting support means.  6. Cooling circuit according to claim 1, characterized in that it further comprises a pair of first pipes (94, 96) connected to said upper radiator (88) for circulating in this radiator an engine coolant; and a pair of second pipes (70, 72) connected to said lower radiator (64) for circulating hydraulic fluid through this radiator.  7. Liftable radiator assembly intended for beech used in the engine compartment of a sliding direction loader comprising a pair of uprights (26), this assembly being characterized in that it comprises a shelf (86) extending laterally , this shelf being of a type of construction forming a generally rectangular frame; means (100, 102) which support one end of said shelf so that it can tilt about a substantially longitudinal axis (104) between raised and lowered positions; a radiator (88) supported inside said shelf; an oscillating latch (110) mounted on said shelf (86) for engaging with a notch (112) formed in said opposite post (26) and disengaging from this notch; and an actuating rod (106) connected to said latch, said actuating rod having a folded end which can be engaged, in a storage position, in an opening (116) formed in said shelf (86) and in an opening (118) formed in said first upright (26) for retaining said shelf (86) in a raised position.  8. liftable radiator assembly according to claim 7, characterized in that it further comprises a second side shelf (62) having the construction of a generally rectangular frame and which extends below said first shelf ( 86); means (74, 76) which articulate a first end of said second shelf (62) to said first upright (26) to allow it to tilt about a substantially longitudinal axis (78); a flange (84), fixed to said other upright (26) for supporting said second shelf (62) in a lowered position; a second air / liquid heat exchanger (64) mounted on said second shelf (62); and a hook (122) for connecting said second shelf (62) to said first shelf in the raised position.  9. liftable radiator assembly according to claim 7, characterized in that it comprises a handle (120) fixed to said first shelf (86).  10. Liftable radiator and oil cooler assembly, intended to be mounted between a pair of uprights (26) in the engine compartment of a loader & sliding steering, characterized in that it comprises: upper transverse shelves ( 86) and lower (62) positioned in superimposed positions, each shelf being of a construction forming a generally rectangular frame; means (100, 102) which articulate a first end of said upper shelf (86) to allow it to tilt about a first axis (104) substantially longitudinal, between raised and lowered positions; an oil cooler (64) mounted on said lower shelf (62); a flange (84) fixed to the opposite upright (26) for supporting said lower shelf (62) in the lowered position; a latch (110) mounted on said upper shelf (86) for engaging and detaching a notch (112) formed in said other upright (26); and an actuating rod (106) connected to said latch (110), this rod having a folded end which can move between a storage position in which it is engaged with an opening (116) of said upper shelf (86) , and a position in which it engages with an opening (118) of said first upright (26) to maintain said upper shelf in a raised position.  11. Liftable radiator and oil cooler assembly according to claim 10, characterized in that it further comprises a handle (120) mounted on said upper shelf (86); and a hook (122) for connecting said upper (86) and lower (62) shelves in a separable manner in said raised position.