GB2158787A

GB2158787A - Chassis frame for service vehicles

Info

Publication number: GB2158787A
Application number: GB08512396A
Authority: GB
Inventors: Walter Hawelka; Hermann Staudinger
Original assignee: Konrad Rosenbauer KG
Current assignee: Konrad Rosenbauer KG
Priority date: 1984-05-18
Filing date: 1985-05-16
Publication date: 1985-11-20
Also published as: IT1208545B; GB8512396D0; ZA853638B; NL8501436A; BE902420A; FR2564407B1; DE3517287A1; CH667626A5; GB2158787B; IT8520762A0; FR2564407A1; JPS618064A

Abstract

A chassis frame particularly suitable for fire service vehicles comprises a pair of main bearers (51) extending longitudinally and spaced transversely of the vehicles, each including at least one angled portion (52) suitably dispersed between the front and rear axles (4, 5) and extending transversely of a longitudinal direction (38). Suitably the angled portions (52) extend lengthwise, widthwise and heightwise of the vehicle and present an obtuse angle of less than 180 DEG C towards the wheels. Engine mounting means are situated rearwardly of the front axle (4) and an engine output shaft is positioned above the axles (4, 5) and between the axes (4, 5) and upper portions of the wheels (6). See also fig. 1 for a simpler embodiment. An intermediate portion of the frame between the wheels may be arranged as a portal. The invention facilitates adaptation to different service vehicle requirements, the installation of drive transmissions and service equipment such as fire fighting equipment whilst allowing for ease of access and flexibility in use. <IMAGE>

Description

SPECIFICATION Chassis frame for service vehicles The invention relates to a chassis frame for service vehicles, in particular, but not exclusively, for fire service vehicles, comprising an uninterrupted vehicle frame having at least one main bearer extending in the longitudinal direction of the vehicle, which accommodates two driving axles spaced apart in longitudinal direction from each other, a driving engine, a driver's cab, transmissions and other ancillary equipment.

Different chassis frames are already known for service vehicles and in particular for fire service vehicles. It is known that the driving engine for propulsion on land of such vehicles may be installed between continuous stringers or bearers and substantially above these in the region above or forwardly of the front driving axle or in the region of or rearwardly of the rear driving axles.

However, in the case of chassis frames utilised at this time, which derive from the production of series chassis frames for conventional commercial vehicles, such as tippers, long-distance cargo vehicles or the like, it is possible only with great difficulty to adapt these by uncomplicated means to the different service requirements and conditions of service vehicles such as fire service vehicles.

The chassis frames supplied in normal production series commonly require extensive adaptation and reconstruction work, in order to comply approximately to the requirements specified in the sphere of service vehicles.

In another known chassis frame for a fire service vehicle - corresponding to the research report of the Federal Minister for Research and Technology of the Federal Republic of Germany regarding optimised life-saving and fire-fighting with integrated technical assistance of July 1978, also referred to as an "Orbit" study - the driving engine for the 4 x 4 vehicle (two axles having single wheels in each case and all wheels being driven) is arranged substantially above the front driving axle. Its drive output is positioned below the upper margin of the chassis frame structure. This arrangement obstructs access to the driving engine, since accessibility from beneath is made difficult by the driving axle, the axle transmissions and the drive shafts.

At the same time, the vibrations as well as the waste heat of the driving engine are transmitted into the superjacently situated driver's cab, thereby complementarily increasing the stress on the service personnel which is already under considerable strain in the course of an operational trip.

It is also already known that the securing devices for a driving engine may be installed between the two driving axles of a chassis frame - in accordance with Patent Specification No. 885 689. The driving engine is suspended from above between the two main bearers of the chassis frame structure, so that its upper portion is situated below the upper margin of the main bearers of the chassis frame structure. Although an advantageous position of the centre of gravity of the engine on the chassis frame structure is obtained thereby, it is hardly possible however to maintain the required ground clearance, since the drive output of the driving engine is substantially already at the same level or below that of the axle centre of the driving axles. In particular, the incorporation of the distributor gearbox is rendered difficult.

It is an object to devise a chassis frame for service vehicles, which is generally adapted for service vehicle application and allows for manifold possibilities of variation regarding the desirable propulsion method, the position of the centre of gravity and the superstructures.

According to the invention it is also possible furthermore that the main bearer is formed with an angled portion, and that the frame members situated at either side of the angled portion subtend an angle facing the wheels smaller than 180 .

Thanks to the angular deflection and/or cranking of the main bearer or bearers, it is possible to make available a space between two main bearers or below the two main bearers, so that an adequate ground clearance is obtained and that it is possible despite this to adapt the positioning or fastening of the various equipment elements, for example of the fire extinguisher pump, a tank and the like on the main bearer to different operational conditions or customers' requirements.

Suitably the chassis frame structure is formed by main bearers extending in the longitudinal direction of the vehicle and mutually spaced apart transversely and the angled portion occurs in the region of and forwardly of the front driving axle whereby a main bearer section extending forwardly from the angled portion extends forwardly from the front driving axle downwardly towards a wheel support plane. This form of the main bearers allows advantageous positioning of ancillary equipment below a driver's cab floor, apart from a reinforcement of the structure in the front section.

According to another feature of the invention the main bearers are arranged in a plane substantially parallel to a wheel support plane of the wheels and sections extending forwardly of the angled portions from rearwardly of the front wheels and over the front axle have a smaller transverse spacing than sections of the main bearers rearwardly of the angled portions and preferably extending to behind the rear driving axle. It is possible thereby to make available sufficient space in the area of the front driving axle to obtain a small turning circle and at the same time, and the drive output of the driving engine immediately adjacent to the front driving axle may extend into the space below the upper margin of the chassis frame structure.A further advantage is that the chassis frame structure is wider in the area of the rear driving axle which may contain an extinguishing agent pump and/or an extinguishing agent tank, and that a wider support area is thus obtained for superstructures.

Suitably the chassis frame structure is formed by main bearers extending longitudinally and spaced transversely of the vehicle, the main bearers being formed with respective angled portions disposed between the front and rear axles and extending transversely of a longitudinal direction of the main bearers.

Preferably the angled portions extend lengthwise, widthwise and heightwise in relation to the vehicle. These forms of the main bearers provide the unexpectedly uncomplicated possibility to install the driving engine and the equipment cabin or the equipment receiving modules at as low as possible a position, thereby securing satisfactory lateral stability and centre of gravity position. Beyond this, the accessibility of the items of equipment and their stowage, are facilitated and simplified.

It is also possible for the main bearers to overbridge a section between the front and rear driving axles in the manner of a portal, so that for example equipment modules or extinguishing agent tanks or the like may simply be unloaded at the point of operational application and that the unloaded chassis may be utilised for replenishment drives for fetching different items of equipment.

It is advantageous if a securing means for a fire extinguisher pump is situated on the main bearer section projecting over the front driving axle and following the angular offset, since this simplifies access to the fire extinguisher pump and its operation.

In the embodiment mounting means for the driving engine are situated rearwardly of the front axle and an output shaft of the driving engine is positioned above the driving axles and between the driving axles and upper portions of the wheels.

Suitably the mounting means are situated between the front and rear axles. The advantages of this unexpectedly simple solution consist in that an advantageous combination is obtained between the requirements in respect of the position of the centre of gravity and the accessibility of the engine and the preponderantly unhampered possibilities of variation for different superstructures on service vehicles of this nature. A satisfactory accessibility from the top as well as from the bottom is assured by the arrangement of the driving engine, which is relatively unimpeded by the axle drives or intermediate gearboxes or the like. At the same time, the appropriate vertical position allows of driving both axles via drive shafts by means of a central powerdrive transmission, and thereby of providing an allwheel drive and securing an appropriate ground clearance.Another positive aspect of this solution consists in that the driving engine hardly bothers and driver's cab and thus the service personnel with vibrations, noise generation or thermal radiation. A widely adaptable fundamental structure of the chassis frame, which may be adapted in an uncomplicated manner for different operational purposes of a service vehicle, is thus obtained.

It is an advantageous arrangement the mounting means for the driving engine are installed in sections of the main bearers, rearwardly of the angled portions and that the output shaft of the driving engine and that of a gearbox are transversely spaced apart from on opposite sides of a longitudinal axis of the vehicle by approximately the same amount. The distribution of the driving forces to the separate driving axles, as well as the incorporation of the drive shafts, are facilitated by the po- sitioning of the drive outputs.

Provision is made according to another form of embodiment of the invention that the transmission drive output for the front and rear driving axles as well as the associated power transmission means and the axle drives are each designed to transmit the total torque of the transmission drive output. It is thus possible in an unexpectedly uncomplicated and advantageous manner for a service vehicle to select the drive method corresponding in optimum degree to driving conditions, namely front drive, rear-wheel drive or all-wheel drive.

It is also advantageous if the front and rear driving axles each have two wheels and are suspended on the main bearers or an intermediate frame via leaf springs, since the support surface available may thereby be exploited satisfactorily for transmission of frictional forces and a large support surface may be obtained. Satisfactory lateral location of the axles may be obtained by installing leaf springs between the main bearers and the axles.

In accordance with the invention, the two driving axles may also be suspended on the chassis frame structure via fluid-operated spring elements, a venting and filling valve being situated between a pressure-fluid supply system and the pressure-fluid spring elements being operatively coupled with several actuating members distributed about the vehicle. It is thus possible upon taking bends at high speed to tip the body around its longitudinal axis against the action of centrifugal force by appropriate application of pressure to the spring elements, and it is also possible to adapt the distance of the bodywork or of the chassis frame structure from the wheel support plane to the different operational conditions such as travel on metalled roadways or cross-country travel or stoppage during utilisation.By lowering the chassis frame structure during operation, the overall height of the vehicle may be reduced, and access to the items of equipment may also be facilitated. If several actuator units are moreover installed on the chassis frame structure or the service vehicle for actuation of the venting and filling valves and of the spring elements, the required position of the chassis frame structure with respect to the wheel support plane may be established notwithstanding the momentary station of the operative.

Furthermore, a carrier framework on which for example are situated air filters, compressed air tank, and/or fuel or lubricant tanks and possibly a spare wheel is suitably arranged rearwardly of forward angled portions of the bearers generally in a plane extending transversely to the longitudinal direction of the vehicle and at right angles to the wheel support plane, whereby it is possible for the space between the main bearers to be kept unoccupied for installation of equipment or for the drive shafts or the power-drive transmission and the like.

The items of equipment which commonly have a large volume but are not very heavy may be positioned above the chassis frame structure.

It is also advantageous for disc brakes comprising brake discs placed in oil baths to be installed on the driving axles, since these allow of full exploitation of the driving speeds raised thanks to the measures according to the invention, especially on curved sections, but also on straight stretches of road, while nevertheless maintaining an uniform deceleration irrespective of the number of braking actions during a frequently but very brief operational journey.

Provision is made according to another modified embodiment of the invention that a transverse impact guard (or "Mini" gate) be secured in the portion of the chassis frame structure situated behind the rear driving axle on the main bearer and that the impact guard be displaceable with respect to the main bearer around an axis extending transversely to the longitudinal direction of the vehicle, in particular at right angles to the support plane. It is possible thereby to install items of equipment as low as possible on the chassis frame structure, or to provide an extinguishing fluid pump which is easily accessible and has a lesser access height.

These items of equipment installed at a low level are still protected against damage by the impact guard which may be removed in the operational case, to establish accessibility.

In this connection, it is also advantageous if a trailer coupling is installed on a transverse bearer of the impact guard, since the advantages of the incorporation of a trailer coupling may thereby be combined with those of impact protection.

Finally, it is also possible within the scope of the invention that the securing means for a fire extinguisher pump may be arranged in preferably pendant manner on a frame member which is vertically displaceable with respect to the main bearers, the vertical positioning of the extinguishing fluid pump not being adversely affected by the frame height.

The invention will now be described, by way of example, with reference to the accompanying partly diagrammatic drawings, in which: Figure 1 is a diagrammatic side elevation of a service vehicle chassis frame according to the invention with the driving engine arranged thereon; Figure 2 is a plan view of the chassis frame of Figure 1, Figure 3 is a diagrammatic side elevation to a reduced scale of a modified embodiment of a chassis frame according to the invention; Figure 4 is a plan view of the chassis frame of Figure 3;; Figure 5 is a diagrammatic side elevation of a further embodiment of a chassis frame according to the invention comprising a framework overbridging a section between the two driving axles in the manner of a portal, Figure 6 is a plan view of the chassis frame of Figure 5, Figure 7 is a diagrammatic side elevation of a yet further embodiment of a chassis frame according to the invention with chassis frame structure elements staggered in the direction of the support plane; Figure 8 is a diagrammatic side elevation of a service vehicle comprising a drive system according to the invention; Figure 9 is a plan view of the service vehicle of Figure 8; Figure 10 is a fragmentary end view taken along lines X-X of Figure 9 of the arrangement of an auxiliary assembly on the chassis frame structure;; Figure ii is a fragmentary sectional view taken along line XI-XI of Figure 9 of the arrangement of a transmission module, and Figure 12 is a fragmentary partly sectional view taken on line XII-XII of Figure 9 of the arrangement of the driving engine with respect to the chassis frame structure.

The service vehicle 2 of Figures 1 and 2, for example a fire service vehicle, comprises a chassis frame 1. The chassis frame 1 comprises a chassis frame structure 3 which is borne on a wheel support plane 7 or road surface via driving axles 4, 5 and wheels 6 mounted on the axles 4, 5. The chassis frame structure 3 extends from a region forward of the front driving axle 4, over the two driving axles 4, 5 and into a region projecting rearwardly beyond the rear driving axle 5. A driving engine 8 is installed on the chassis frame structure 3 by means of securing means 9, at a location between the two driving axles 4, 5.The securing means 9 are so far fastened to the chassis frame structure 3, in such manner that a drive output 10 of the driving engine 8 is positioned above the axles 4, 5 and between the driving axles 4, 5 and upper extremities 12 of the wheels 6 oppositely situated to lower support points 11 of the wheels 6.

The drive output 10 is also situated below top edges 13 of main bearers 14 forming the chassis frame 3. In the region of the rear driving axle 5, the main bearers 14 have a lower recess consisting of two angular deflections, followed by rearward frame members 17 of the main bearers 14 staggered towards and extending generally parallel to the wheel support plane 7. A fire extinguisher pump 18 is supported on the frame members 17 of the main bearers 14. Access to the fire extinguisher pump 18 or to another extinguishing fluid pump or to any assembly requiring manual access, for example a hose reel or the like and mounted on the frame member 17, is facilitated because the frame members 17 of the main bearers 14 are downwardly staggered in the direction of the wheel support plane 7.

The frame members situated at either side of the two angular deflections 15 and 16 subtend an angle 19 which is less than 180 .

The driving engine 8 is flange coupled directly to a transmission gearbox 20, which is transmissively coupled to axle drives 23, 24 via power transmission means 21, 22. The power transmission means 21, 22 may be formed by UJ (universal joint) shafts, their dimensioning being so selected that each of the power transmission means 21, 22 can transmit the total torque of the driving engine 8.

The transmission of power between the gearbox 20 and the axle drives 23, 24 may alternatively be via hydraulic coupling, for example via hydraulic pumps, hydraulic pipes and hydraulic motors.

As also apparent from Figure 1, the driving axles 4, 5 are connected to the chassis frame 3 via leaf springs 25. The wheels of the front driving axle 4 are arranged to be steered by means of a steering wheel 26. As shown in Figure 1 an implement carrier frame 29 is situated between a driver's cab 27 installed forwardly on the chassis frame 3 and a rearward equipment or implement cabin 28. An air filter 30, a compressed air tank 31, a spare wheel 32 arid a fuel or lubricant tank 33, may for example be installed on the implement carrier frame 29. The space between the main bearers 14 of the chassis frame 3 is thereby kept free for the installation of the driving engine 8, of the transmission gear 20 and a power transmission means 34, e.g. a Cardan shaft for coupling a PTO (power takeoff) 35 to the first extinguisher pump 18 for direct drive of the pump 18 from the driving engine 8.

As seen in Figure 2 the driving engine 8 has its central longitudinal axis 36 laterally offset with respect to a central longitudinal axis 38 of the vehicle by a distance 37. The axes of output drives 39 for the driving axles 4, 5 directed parallel to the longitudinal axis 38 of the vehicle are offset with respect to the longitudinal axis of the vehicle 38 by a distance 40 on the opposite side of the central longitudinal axis 36, and the power transmission means 21, 22 are situated between the two main bearers 14 of the chassis frame 3.

As further seen in Figure 2 the chassis frame 3 has two angular deflections 41, 42 in the region behind the front driving axle 4, and in the plane extending parallel to the wheel support plane 7 producing an offset of the two main bearers 14, such that the spacing between the main bearers is increased rearwardly thereby in the region following the wheels 6 of the front driving axle 4 as compared to the spacing of the bearers extending between the wheels and over the front driving axle 4. The installation of the driving means as well as of the transmission is facilitated thereby. Each of the two angular deflections 41, 42 has an angle 43 which is less than 180". Drum brakes 44 are situated between the driving axles 4, 5 and the wheels 6.

In the modified embodiment of chassis frame 45 for a service vehicle 2 is illustrated in Figures 3 and 4 and as apparent from Figure 3 in particular, the chassis 45 comprises a chassis frame 46 of which a front frame section 47 extends in the region of the front wheels 6 facing away from the wheel support plane 7 and above the front driving axle 4. Another frame member 48 extending rearwardly beyond the rear driving axle 5 is upwardly displaced from the frame member 47 with respect to the wheel support plane 7 by approximately the height 49 of a superstructure of the vehicle. As apparent from Figure 3 and Figure 4, the frame members 48 extend within upper marginal areas of the superstructures of the service vehicle 2. The rear driving axle 5 is borne by the rear frame member 48 of the main bearer 51 forming part of the chassis frame 46 via a columnar bearer 50.The frame members 47 and 48 of the main bearers 51 are interconnected by frame members 52 extending obliquely downwardly and forwardly behind the front wheels 6, an angular transition 53 being provided in each case between the frame members 47 and 52, and 48 and 52, respectively. As apparent from Figures 3 and 4, this is a spatial angular deflection in that the frame members also have angular offsets 53 not only in their plane extending parallel to the longitudinal axis 38 of the vehicle and vertically to the wheel support plane, but also have angular transitions 54, 55 in the plane extending parallel to the wheel support plane 7. The main bearers 51 are thus spatially cranked and forward frame members 47 are both lowered and more closely spaced in relation to the frame members 48.Furthermore, the chassis frame 46 has a frame member 56 extending at the level of the frame members 47 but approximately along the longitudinal axis 38 of the vehicle, which extends centrally between the wheels of the front and rear driving axles 4 and 5.

The frame member 56 accommodates the driving engine 8 and a transmission 20 as well as - partially - an extinguishing agent tank 57 denoted by thin lines. The extinguishing agent tank 57 is installed in freely movable manner with respect to the chassis frame 46, via resilient securing elements 58, on the frame member 56 and on the frame members 48 of the main bearers 51. These securing elements 58 may be formed by rubber spring elements or leaf springs or analogous devices.

A driver's cab 27 is supported on the chassis frame 46 in the region of the forward frame members 47 and 52, whereas implement cabins or equipment modules 59 are suspended in simple manner on the frame members 48 of the main bearers 51 running through the upper marginal sections. Thanks to this suspension of the equipment modules 59, these are not fouled by frame members running through at the bottom and may be installed as close as possible above the wheel support plane 7 according to the ground clearance required. Access to the items of equipment and to the implements is considerably facilitated thereby.

It is possible by uncomplicated technical means, for example as shown for a middle equipment module 59, by installing an intermediate frame 60 and a vertical displacement drive 61, e.g. a pistoncylinder system, for the equipment module 59 to be lowered at the site of operation to the lowered position illustrated by pecked lines, in guideways of the intermediate frame 60, or to set the same down altogether, so that the service vehicle may if appropriate be utilised to fetch other equipment modules. Instead of installing the vertical displacement drives 61 and the intermediate frames 60, the possibility is also available to displace the driving axle 5 along the columnar bearer 50 vertically with respect to the frame member 48 of the main bearers 51 by means of diagrammatically indicated vertical displacement drives 62 thereby reducing the access height to the equipment module 59 and to a fire extinguisher pump 18 possibly installed in the area of the frame member 56 projecting above the rear driving axle 5.

The spatial offset of the main bearers 51 allows for accommodation of the front driving axle 4 as well as an area of unconfined steering swing for the front wheels 6 and thus for an advantageous turning circle of the service vehicle. It is also possi ble to arrange for steering not only of the front wheels 6 but also of the rear wheels to secure more efficient cornering with economical tyre wear.

For the sake of clarity of illustration, claddings and the like are omitted from the illustration of Fig I ure 3, and the driver's cab 27 and some equipment modules 59 are omitted from Figure 4, and the in corporation of the fire extinguisher pump 18 is in dicated in a diagrammatical manner only. The connection between the chassis frame 46 and the cabins, modules or other superstructures com monly consists of resilient intermediate elements.

Furthermore, it is also possible in this form of the chassis frame 46 for the output drive 10 of the driving engine 8 to be installed without difficulty in a a position vertically between the driving axles and the upper extremities of the wheels. The frame member 56 may to this end be downwardly or up wardly offset or cranked at right angles to the wheel support plane 7 with respect to the frame members 47.

In the embodiment of Figures 5 and 6, a chassis frame 63 is provided with two main bearers 64 which overbridges the area between a front driving axle 4 and a rear driving axle 5 in the manner of a portal. To this end, the main bearers 64 are cranked substantially vertically downwardly and laterally inwardly in the opposed regions rear wardly of the front and forwardly of the rear axles 4 and 5, the main bearers 64 having two oppositely directed angular transitions 65, 66 which jointly produce the cranked form. As a result the frame members 67, 68 extend in the region of the front and rear driving axles 4 and 5, between the wheels 6 of these axles and immediately above the driving axles 4, 5. This facilitates the fastening of the driv ing axles 4, 5 and the assemblies required.In the section situated between the driving axles 4, 5, the portal-like arrangement of the main bearers 64 en ables equipment modules 59 to be suspended or hung from the chassis frame 63 to provide advan tages of accessibility and lesser withdrawal heights.

In the chassis frame 63 of Figures 5 and 6, the driving engine 8 may advantageously be installed above the rear driving axle 5. It is unnecessary to install an additional supporting structure for the driving engine 8 since the engine may be sup ported directly on the frame member 68. At the same time, a fire extinguisher pump 18 or another extinguishing fluid pump or the like may be in stalled on the frame members 68 or on a frame member 69 forming a downwardly displaced ex tension thereof. A stowage space for instruments and devices for example for first-aid or salvage may be provided in the region above the driving axle 5. The extinguishing fluid tank 57 may be sus pended in the same manner as the equipment modules 59, but centrally between these, between the two main bearers by means of transverse bear ers.A driver's cab 27 is suitably installed in the section above the front driving axle 4.

In the embodiment of Figure 7 a chassis frame 70 is cranked in the direction of the wheel support plane 7 between the front and rear wheels 6.

Frame members 71 of the two main bearers 72 extending mutually parallel, are lowered downwardly in the direction of the wheel support plane between the front driving axle 4 and the rear driving axle 5, for which purpose the main bearers 72 are formed with two angular transitions or a cranked section in the region of the two driving axles and their wheels which are turned towards each other to extend between the pairs of wheels and over the axles. The driving engine 8 as well as a fire extinguisher pump 18 are secured to the main bearers 72 via simple fastening devices, and the equipment modules or the driver's cab 27 or other superstructures, such, for example, as turntable ladders, elevating platforms or the like may be installed directly on the main bearers of the chassis frame 70.A reduced overall height of a service or fire service vehicle 2 is obtainable by displacement of the frame member 71 in the direction of the wheel support plane 7.

As also shown in Figure 7 pressure fluid spring elements 73, for example pneumatic springing elements, may be arranged between the driving axles 4, 5 and the chassis frame 70. These pressure fluid spring elements 73 being connected to a pressure fluid supply system 74 via a bleed and filling valve 75. For actuation of the bleed and filling valves 75, actuating members 76 are provided, for example in the driver's cab 27 or at different points of the superstructure, for example in the area of the fire extinguisher pump 18 or in the area of equipment modules.

It is thereby possible by utilising the pressure fluid spring elements 73 to reduce the already very low height of the service vehicle by lowering the chassis frame 70 closer to the wheel support plane 7.

In all of the embodiments of Figures 1 to 7, the form of the chassis frame allows mounting of the driving engine 8 at an appropriate position with respect to the chassis frame with the drive 10 located above the axles and between the driving axles and the upper extremities of the wheels 6, as illustrated diagrammatically in the drawings. The construction and form of the implement cabins or equipment modules is freely selectable. The equipment modules or implement cabins may be constructed from sectional tubing with external claddings, pivot or sliding doors or roller blinds.

Furthermore, as indicated in Figure 4 the service vehicles 2 or fire service vehicles according to the invention, may also be equipped with impact or collision guards 77. A trailer coupling 78 may be situated on the impact guard 77. So that access to intake couplings or the like is not obstructued, for example if the fire extinguisher pump 18 is installed as deeply as rendered possible by the construction of the chassis frame according to the invention, the impact guard 77 may be arranged to be pivoted around an axis at right angles to the wheel support plane 7 as shown by pecked lines, together with the trailer coupling 78, upon reaching a site of operation.Instead of a structure of this kind, the bearer forming the impact guard may however be arranged to be removed completely by withdrawing locking bolts, or pivoted around other axes, such as by parallelogram lever systems or the like.

A service vehicle 101, comprising a chassis frame 102, a driver's cab 103 and an utility superstructure 104, which may also contain an extinguishing fluid tank 105, is illustrated in Figure 8.

The driver's cab 103 and the utility superstructure 104 are shown by thin outlines only and cut away so that the propulsion system according to the invention for a service vehicle of this kind may be illustrated more clearly.

As apparent from Figures 8 and 9, the vehicle frame 102 comprises two main bearers 106, 107 extending parallel to each other in the longitudinal direction of the vehicle. The main bearers 106, 107 of the vehicle frame 102 are supported via conventional springing means, for example leaf springs or compressed air springs, on a steerable driving front axle 108 and a rear driving axle 109. The two driving axles 108, 109 carry wheels 110 with single tyres. The vehicle frame 102 houses an auxiliary unit 112 formed by an extinguishing fluid pump 113 in the region 111 projecting forwardly beyond the front driving axle 108 and between the two main bearers 106, 107. The extinguishing fluid pump 113 is transmissively coupled via a Cardan shaft 114 acting as a driving connection to the transmission module 115 similarly situated between the main bearers 106, 107.The Cardan shaft 114 is then coupled to a PTO (power takeoff) 116 of a shift-gear transmission 117. The transmission module 115 has a converter gear 118 apart from the shift-gear transmission 117 and intermediate inter-axle gearbox 119, housed in the same casing.

The transmission module 115 is borne on a transverse bearer 121 secured on the two main bearers 106, 107 via oscillation-damper elements 120.

As more clearly apparent from Figure 8, output drives 122, 123 of the inter-axle gearbox 119 are coupled via Cardan shafts 124, 125 to axle drives 126, 127. An all-wheel drive vehicle is obtained thanks to this construction, in which the two driving axles 108 and 109 may be driven independently of each other. The rating of the Cardan shafts 124, 125 as well as of the intermediate inter-axle gearbox 119 and of the axle drives 126, 127 is so selected that the total torque available for propulsion of the service vehicle 101 may be transmitted via either of the two Cardan shafts 124 or 125. The service vehicle 101 may be operated at will with front-wheel drive, rear-wheel drive or all-wheel drive.

An input shaft 128 of the transmission module 115 is coupled to a driving engine 130 via another Cardan shaft 129.

The driving engine 130 is installed on the main bearers 106, 107 in an area 131 of the vehicle frame 102 projecting rearwardly beyond the rear driving axle 109. An output drive 132 of the driving engine 130 is situated at the level of an upper margin 133 of the vehicle frame 102.

Thanks to the construction of the propulsion system and the arrangement of the individual assemblies, the vehicle frame 102 has an approximately identical load distribution in the areas 111, 131 projecting beyond the two driving axles 108, 109.

Thanks to the spacing between the two main bearers 106, 107, the driving engine 130, the transmission module 115 and the auxiliary assembly 112 may be installed at a small distance from the wheel support plane 134. Space for superstructures and cabin sections is provided between the two driving axles 108, 109, above the top edge 133 of the main bearers 106, 107, as well as sidewardly thereof. An extinguishing fluid tank 105 may thus advantageously be installed in the area between the two driving axles 108, 109. The weight of the transmission module 115 and of the extinguishing fluid tank 105 is then divided approximately evenly between the two driving axles 108, 109, thereby securing a neutral driving behaviour of the service vehicle 101.

It is also possible, for the driving engine 130 to be installed for example right at the transmission module 115 or between the transmission module 115 and the rear driving axle 109, and to install the extinguishing fluid tank 105 in the rear section of the service vehicle 101.

An installation of this kind of the driving engine is denoted by pecked lines in Figure 8.

The mounting of the auxiliary assembly 112, comprising an extinguishing fluid pump 113, is shown, for example, in Figure 10. The extinguishing fluid pump is borne on an intermediate frame 136 via oscillation-damper element 135, and the intermediate frame is located in the inner side of the main bearers 106, 107 over rollers 137. The intermediate frame 136 may be secured to the main bearers 106, 107 at the corresponding extreme po- sitions by means of locking bolts 138.

After pivoting a panel 139 in the front of the driver's cab 103 as denoted by an arrow 140, it is thus possible to place the auxiliary assembly 112 comprising the extinguishing fluid pump 113 in the space present forwardly beyond the front 141 of the vehicle.

If the extinguishing fluid pump is mounted on an intermediate frame 136 of this kind and not fixedly on the vehicle frame 102, the Cardan shaft 114 is constructed as a telescopic shaft as diagrammatically denoted in Figure 9, to allow for the auxiliary assembly 112 being pushed outside and inside of the vehicle without interruption of the transmission line.

Instead of the extinguishing fluid pump shown in Figures 8 to 10, it is also possible to install any other and optional auxiliary assembly, for example a current generator, a hydraulic system or the like.

It is also possible to provide any other kind of mounting for the auxiliary assembly instead of the intermediate frame 136 movable by means of rollers, for example a parallelogram linkage of levers which is secured on the main bearers 106, 107 of the vehicle frame 102.

Figure 11 shows the mounting of the transmis sion module 115 between the two main bearers 106 and 107 of the vehicle frame 102. As apparent, the transverse bearer 121 is of U-shaped form and has its two free extremities connected via the oscillation damper elements 120 to the main bearers 106, 107 of the vehicle frame 102.

This allows the transmission module 115 to move under resilient damping in several spatial directions with respect to the vehicle frame 102.

It is shown in Figure 12 that the driving engine is borne via engine bearers 142 and vibration damper elements 120, equally on the two main bearers 106, 107 of the vehicle frame 102. The engine bearers 142 are so constructed that the output drive 132 of the driving engine 130 is positioned approximately in the area of the upper margins 133 of the main bearers 106, 107 or of the intermediate frame placed thereon.

As apparent from Figures 8 and 9, the two main bearers 106 and 107 extend mutually parallel throughout the vehicle length and have an angular offset 143 only in a plane extending at right angles to the wheel support plane 134. The section 111 of the vehicle frame 102 following the angular offset 143 and projecting even farther forward from the front driving axle 108 is inclined forwardly and downwardly in the direction of the wheel support plane 134, which facilitates the incorporation of an auxiliary assembly 112 such as the extinguishing fluid pump 113 in the present case. Thanks to the inclined extension of the section 111 of the vehicle frame 102, and as also apparent from Figures 9 and 10, the withdrawal of the auxiliary assembly 112 beyond the front end side of the service vehicle 101 is possible in a simple manner.

Another advantage of the form of the main bearers 106 and 107 passing without any angular deflection throughout a plane extending parallel to the wheel support plane consists in that the front driving axle 108 as well as - if required - the rear driving axle 109 may be constructed to be steerable in order to facilitate manoeuvering operations with the service vehicle 101.

The form of the main bearers 106, 107 of the vehicle frame 102 is also freely selectible within the ambit of the invention. Instead of one-piece continuous main bearers, it is also possible to utilise multisectional main bearers which may for example in the area of the angular offset or else in other intermediate areas of their longitudinal extension may be joined together by means of bolted joints.

Instead of application to fire service vehicles, the propulsion system according to the invention may equally and advantageously be utilised for any other category of service vehicles, for example such as elevator vehicles, public utility vehicles or the like.

The direction of travel is commonly denoted by an arrow 144 in the drawings.

Claims

1. A chassis frame for service vehicles, in particular fire service vehicles, comprising an uninterrupted vehicle framework which has at least one main bearer extending in the longitudinal direction of the vehicle, which accommodates two driving axles spaced apart from each other in longitudinal direction, a driving engine, a driver's cab, transmissions and other ancillary equipment, in which the main bearer is formed with an angled portion and that frame members situated at either side of the angled portions subtend an angle facing the wheels which is smaller than 180 .

2. A chassis frame according to claim 1, in which the chassis frame structure is formed by main bearers extending in the longitudinal direction of the vehicle and spaced apart from each other transversely to the direction of travel, and that the angled portion is formed in the region of and forwardly of the front driving axle whereby a main bearer section extending forwardly from the angled portion extends forwardly from the front driving axle downwardly towards a wheel support plane.

3. A chassis frame according to claim 2, in which the main bearers are arranged in a plane substantially parallel to a wheel support plane of the wheels, and sections extending forwardly of the angled portions from rearwardly of the front wheels and over the front axle have a smaller transverse spacing than sections of the main bearers rearwardly of the angled portions.

4. A chassis frame according to claim 1, in which the chassis frame structure is formed by main bearers extending longitudinally and spaced transversly of the vehicle, the main bearers being formed with respective angled portions disposed between the front and rear axles and extending transversely of a longitudinal direction of the main bearers.

5. A chassis frame according to claim 4, in which the angled portions extend lengthwise, widthwise and heightwise in relation to the vehicle.

6. A chassis frame according to claim 4, in which the main bearers overbridge a section between the front driving axle and the rear driving axle in the manner of a portal.

7. A chassis frame according to claim 2, in which a securing means for a fire extinguisher pump is installed on the main bearer section projecting over the front driving axle and forwardly of the angled portion.

8. A chassis frame according to claim 1, in which the mounting means for the driving engine are situated rearwardly of the front axle and an output shaft of the driving engine is positioned above the driving axles between the driving axles and upper portions of the wheels.

9. A chassis frame as claimed in claim 8, in which the mounting means for the driving engine are situated between the front and rear axles.

10. A chassis frame according to claim 8, in which the mounting means for the driving engine are installed in sections of the main bearers rearwardly of the angled portions and that the output shaft of the driving engine and that of a gearbox are transversely spaced apart from on opposite sides of a longitudinal axis of the vehicle by approximately the same amount.

11. A chassis frame according to claim 1, in which transmission outputs for the front and rear driving axles as well as associated power transmission means and axle drives are each designed for transmission of the total torque of a transmission output drive of the engine.

12. A chassis frame according to claim 1, in which the front and rear driving axles each comprise two wheels and are suspended on chassis frame via leaf springs.

13. A chassis frame according to claim 1, in which the two driving axles are suspended on the chassis frame structure via fluid-operated and spring elements, a venting and charging valve being situated between a pressure-fluid supply system and the spring elements being operatively coupled with several actuating members distributed about the vehicle.

14. A chassis frame according to claim 1, in which a carrier framework is arranged rearwardly of forward angled portions of the bearers generally in a plane extending transversely to the longitudinal direction of the vehicle and at right angles to the wheel support plane.

15. A chassis frame according to claim 1, in which disc brakes comprising brake discs situated within an oil bath are installed on the driving axles.

16. A chassis frame according to claim 4, in which a transverse impact guard is fastened to the main bearers in a region of the chassis frame structure situated rearwardly of the rear driving axle, and the impact guard is displaceable around an axis transverse to the support plane to extend in a longitudinal direction of the vehicle.

17. A chassis frame according to claim 1, in which a trailer coupling is situated on a transverse member of the impact guard.

18. A chassis frame according to claim 1, in which a securing device for a fire extinguisher pump is arranged in pendant manner on a frame member which is vertically displaceable with respect to the chassis frame.

19. A chassis frame for service vehicles substantially as described with reference to Figures 1 and 2,3 and 4,5 and 6,7 or8to 12 ofthe draw- ings.