AU2006246488B2 - A vehicle service area including an adjustable walkway - Google Patents

Description

13676AU ORIGINAL Complete Specification Applicant: Quentin Dean Moore Title: A vehicle service area including an adjustable walkway Address for Service: LESICAR PERRIN, 49 Wright Street, Adelaide, South Australia 5000, Australia The following statement is a full description of this invention, including the best method of performing it known to melus: 2 A vehicle service area including an adjustable walkway The present invention relates to vehicle service areas allowing access to the undersides of vehicles, and more specifically to a service area including a floor, a basement or pit there beneath, and a moveable and height adjustable walkway within 5 the pit for skilled personnel to service a vehicle parked there above. BACKGROUND OF THE INVENTION Various known methods exist for accessing the underside of vehicles for service purposes. For example, vehicle service lifts are a well-known apparatus. Many vehicle owners own vehicle jacks which allow one side of a vehicle to be lifted to 10 allow changing of tires or other maintenance functions. In professional service shops, vehicle lifts are generally significantly larger and provide tracks whereupon the wheels of a vehicle may be placed. The tracks (and the entire vehicle) are then lifted so that the underside of the vehicle is accessible to service personnel. The vehicle is lifted to such a height that service personnel may operate on the underside of the 15 vehicle with comfort and convenience. Such vehicle lifts are generally quite expensive, and while models can be constructed which accommodate a wide variety of different types and sizes of vehicles, it is impractically expensive to construct service lifts which can accommodate every conceivable vehicle size and weight. As an example, fire trucks 20 are often too large and heavy to allow the use of a vehicle lift. Some vehicles may have wheelbases which may be significantly larger than standard vehicles, and these cannot be accommodated by any known vehicle lift. Vehicles such as these are generally serviced by use of a service pit. A service pit is a pit in a service area floor which is sized so that a vehicle can 25 drive over the pit with the vehicle's wheelbase spanning the pit. Service personnel located in the pit and beneath the underside of the vehicle may reach up to operate on the underside of the vehicle. Service pits are often formed by forming a hole in the service area floor extending to the basement, and reinforcing the surrounding basement ceiling. In this case, since the basement floor may be eight or more feet 30 beneath the underside of vehicles parked over the service pits, a raised platform may be provided on the basement floor beneath the service pit to allow service personnel 3 to more easily reach the undersides of the vehicles. Service pits are advantageous n that they are low in cost and maintenance compared to vehicle lifts, and they can be made with a length sufficient to traverse more than one vehicle. Service pits pose a problem in that their floors may not be optimally spaced 5 from the undersides of vehicles parked thereover. Since the ground clearances of different vehicles can vary radically, from a foot or so for sports cars to several feet for trucks, service personnel may need to crouch or stoop in service pits, or may alternatively need to work on stepladders. When service procedures are lengthy, this can be very tiring for service personnel. This is undesirable because fatigue 10 significantly amplifies the chance of accident. Additionally, working in crouched or extended positions for long periods of time can lead to spinal misalignment and other back injuries. Some vehicles are long and have more extensive service areas than others and it can sometimes be quite cumbersome and frustrating for service personnel to have to 15 shift all their equipment in order to service another area of the vehicle, or a further vehicle parked thereover, which may only be a few metres away. This becomes particularly inconvenient when using stepladders and the like at elevated heights in that one needs to dismount the stepladder, shift it to the desired position along the vehicle, and then mount it again. 20 Further still, over time such service areas can become very uncomfortable for workers in that the pit area becomes difficult to clean due to oil spills and the like on the floor, and a general build up of tools and equipment because there is no localised means of storing or carrying such equipment for use. Such service areas also lack adequate aeration which is a problem when using potentially harmful chemicals. 25 Occupational health and safety is therefore also a concern in existing service areas known to the applicant. The need therefore exists for a service walk-way that is capable of quick, easy, and safe movements relative to a vehicle, including vertical movements to increase or decrease the height of the walkway, and horizontal movements to enable access to 30 different areas of a vehicle without having to dismount the walkway. There is also a need for a service area or pit which is able to accommodate such a walkway.

4 It is therefore an object of the present invention to overcome at least some of the aforementioned problems or to provide the public with a useful alternative. SUMMARY OF THE INVENTION Therefore in one form of the invention there is proposed a service walkway 5 adapted for use in a service pit having a longitudinal opening for access to an underside of a vehicle, said walkway being elevated clear of the floor of the service pit and being mounted to a side wall of said service pit. In preference said walkway includes a first frame which is horizontally moveable along the length of the opening, and a second frame which is vertically 10 moveable relative to the first frame. Preferably said first frame includes two longitudinally spaced apart, upright beams having horizontal connecting beams, said upright beams including a lower diagonal component and an upper vertical component. Preferably at least one of said upright beams includes a drive means which 15 when actuated causes said first frame to move horizontally. Preferably said drive means is in the form of a motor adapted to drive a roller which is rotatably mounted to the first frame, said roller being positioned to contact a fixed vertical floor surface of the pit extending along the opening such that rotation of the roller causes said first frame to move relative to the fixed vertical floor surface. 20 In preference said motor is an electro-pneumatic motor capable of driving the roller in both clockwise and anticlockwise motions and thereby provide for movement of the first frame in both directions along the opening. Preferably said first frame is supported at its upper end by a fixed vertical ceiling surface of the pit extending along the opening, said vertical surface being 25 horizontally disposed from said vertical floor surface towards said opening, such that 5 the diagonal component of the upright beams causes said first frame to lean against the ceiling surface whilst maintaining said vertical component in a vertical configuration. In preference said upright beams include rotatable guide rollers which coni act 5 the ceiling and floor vertical surfaces. Preferably said second frame includes two longitudinally spaced apart L shaped beams having a horizontal component and a vertical component, wherein the horizontal component of the L-shaped beams extend transversely across said opening to support a service platform, said L-shaped beams also having horizontal connecting 10 beams. In preference the vertical component of the L-shaped beams and the vertical component of the upright beams are equally spaced apart, parallel and slideably engaged. Preferably said L-shaped beams are connected to a second drive means fixed 15 to the first frame, said L-shaped beams being vertically moveable by way of actuation of said second drive means. In preference said second drive means is in the form of two pneumatic cylinders which are fixed adjacent each upright beam of the first frame, said vertical component of each L-shaped beam being fixed to corresponding pneumatic pistons. 20 in preference actuation of said pneumatic cylinders causes said pistons to raise or lower, thereby raising or lowering the L-shaped beams and platform. Preferably said platform includes a first, second, third and fourth foot pedal, said first foot pedal used to actuate said drive motor to move said platform in one direction along the opening, said second foot pedal used to actuate said drive motor in 25 the opposite direction along said opening, said third foot pedal used to actuate said pneumatic cylinder and thereby raise said pistons, and said fourth foot pedal used to actuate said pneumatic cylinder and thereby lower said pistons. Advantageously said platform includes safety rails around its periphery ar.d at least one access gate.

6 Advantageously said platform includes at least one equipment tray for carrying items. Preferably said platform includes apertures which allow liquid and small material to pass through to an undercarriage beneath the platform, said undercarriage 5 being removable. In a further form of the invention there is proposed a service walkway for use in a service area having a service floor, a service pit sunken therein, and an opening in said service floor for enabling access to a vehicle parked over said opening, said service walkway including a platform restrained to move in a horizontal direction 10 along said opening and a vertical direction with respect to the vehicle. In a still further form of the invention there is proposed a service area including: a service area floor; a service pit beneath the floor; 15 a longitudinal opening in said service area floor enabling access from within the pit to an underside of a vehicle located above said opening; and a service walkway positioned beneath the opening, said service walkway being moveable in a horizontal direction along said opening, and a vertical direction with respect to the vehicle. 20 Preferably said walkway includes a platform upon which a person is adapted to stand when servicing the vehicle thereabove. In preference said service area further includes reinforcing columns in the pit area for supporting the floor thereabove. Preferably said opening includes an equipment stand which is moveable along 25 said opening and easily accessible to a person standing on the walkway. In preference said opening further includes an oil sump which is moveable along said opening for receiving oil from the vehicle, said oil sump further capable of being emptied into an oil storage container within the pit. In preference said pit includes a plurality of air vents for aerating the pit.

,7 In a yet further form of the invention there is proposed a service area including: a service area floor; a service pit beneath the floor; 5 two longitudinal openings in said service area floor enabling access from within the pit to an area above said openings; and a service walkway positioned beneath each opening, said service walkways being height adjustable, and moveable in a horizontal direction along said openings. BRIEF DESCRIPTION OF THE DRAWINGS 10 The accompanying drawings, which are incorporated in and constitute a pArt of this specification, illustrate several implementations of the invention and, together with the description, serve to explain the advantages and principles of the invention. In the drawings: Figure 1 illustrates a side view of a vehicle service area including a pit and a 15 moveable walkway within the pit positioned beneath a truck, in accordance with the present invention; Figure 2 illustrates a top view of the vehicle service area of Figure 1 including two openings each having a moveable walkway located there beneath; Figure 3 illustrates a perspective end view of the moveable walkway of the 20 present invention; Figure 4 illustrates a schematic end view of the moveable walkway of Figure 4; Figure 5 illustrates the same schematic end view of Figure 5 with enlarged perspective views of the upper and lower sliding means; Figure 6a illustrates a front view of the moveable walkway of Figure 4 when in a 25 lowermost position; Figure 6b illustrates a perspective view of the moveable walkway of Figure 4 when in an uppermost position; and 8 Figure 7 illustrates the same front view of Figure 7a with enlarged perspective views of the means for actuating movement of the walkway, and one of the hydraulic pistons which when actuated enables height adjustment; and 5 Figure 8 illustrates a perspective view of the pit area beneath on of the openings of the service area of Figures 1 and 2. DESCRIPTION OF THE PREFERRED EMBODIMENTS The following detailed description of the invention refers to the accompanying drawings. Although the description includes exemplary embodiments, other 10 embodiments are possible, and changes may be made to the embodiments described without departing from the spirit and scope of the invention. Wherever possible, the same reference numbers will be used throughout the drawings and the following description to refer to the same and like parts. The present invention relates to a service area 10 for servicing of one or more 15 vehicles 12, as shown in Figures 1 and 2. The service area 10 includes a service area floor 14, a basement or pit 16 having a plurality of vertical beams 18 for supporting the floor 14 there above, and two longitudinal openings 20 and 22 in the floor 14 which enable access to the underside of a vehicle 12 parked above an opening from within the pit 16. Inside the pit 16 are service walkways 24 and 26 which are 20 moveable to different positions along the respective openings 18 and 20, and are also height adjustable in accordance with the present invention. Figures 1 and 2 illustrate a preferred embodiment of the invention having one pit 16, two longitudinal openings 20 and 22, and an adjustable service walkway 24 and 26 beneath each opening. The pit 16 includes a stairwell 28 which allows access 25 from the service area floor 14, as well as a plurality of air vents 30 which serve to aerate the pit area. It is to be understood that a service area could equally well include a single opening, or even a plurality of openings, depending on individual user requirements. For the purpose of brevity, only one side of the embodied service area 10 will be described given that the other side is identical and is essentially a mirror 30 image. The following description therefore relates to the side of the pit having opening 22 and walkway 26.

9 The opening 22 is of an elongate rectangular shape, having a length spanning almost the length of the pit 16, and a width to allow a vehicle 12 to drive over the opening 22. The width of the opening 22 is obviously less than the minimum span of the vehicle wheels 32. The opening 22 allows skilled personnel 34 standing on the 5 walkway platform 36 to reach up to operate on the underside of the vehicle 12. The fact that the walkway 26 is moveable both horizontally along the length of the opening 22, and vertically with respect to the vehicle 12, provides the user with quick and easy access to different areas of the vehicle 12, or perhaps to a further vehicle parked further down the opening 22, and the ability to adjust the height of the 10 walkway 26 for maximized comfort and least strain when working. The adjustable walkway 26 is shown in Figures 3-7 and comprises a first frame 38 which provides for horizontal movement of the platform 36 along the opening 22, and a connecting second frame 40 which is vertically adjustable with respect to the first frame 38 providing for height adjustment. Only one end of the 15 connecting frames 38 and 40 will be described in detail given that the frame members and connecting means at the other end are substantially identical. The first frame 38 includes two spaced apart, upright beams 42 and 44 connected by at least one horizontal reinforcing beam 46, and the second frame 40 includes two equally spaced apart L-shaped beams 48 and 50. The L-shaped beam 48 20 includes a vertical component 52 which slideably engages the first frame 42, and a horizontal component 54 which extends outwardly from the vertical component 52 to support the platform 36. The L-shaped beams 48 and 50 are also connected by at least one horizontal support beam 56. Although not shown, it is preferable for each of the spaced apart structures to have a plurality of horizontal support beams. 25 The upright beam 42 includes a diagonally extending base portion 58 and an upper vertical portion 60 wherein the vertical length of the upper portion 60 compared with the vertical length component of the diagonal portion 58 is approximately 2:1. Located at the upper end of the vertical portion 60 is a bracket having a horizontal surface 62 to which is mounted a horizontal roller 64 using bolt 66. The roller 64 has 30 a guide disc 68 fixed thereto. A ceiling beam 70 runs along the length of the pit 16 adjacent the opening 22, and the side of the horizontal roller 64 abuts against a vertical surface 72 of the ceiling beam 70, which also has a horizontal edge 74 10 alongside which the guide disc 68 extends. In other words, the lower edge of the ceiling beam 70 is received at the junction between the disc 68 and the roller 64. This is shown most clearly in the upper enlarged view of Figure 5. Similarly, at the lower end of the diagonal base portion 58 is a further bracket 5 having a vertical surface 76 to which is mounted a vertical roller 78 and an associated guide disc 80. The side of the vertical roller 78 abuts against a raised horizontal floor surface 82 while the disc 78 extends alongside the raised floor's vertical edge 84. The first frame 38 therefore slideably engages the ceiling beam 70 at its upper end, and engages the raised floor surface 82 at its lower end. This configuration 10 allows the frame 38 to be moveable along these fixed structures whilst being supported between them. Those skilled in the art would realise that having a diagonal portion 58 at the base of the frame causes the frame 38 to lean against the ceiling beam 70, thereby maintaining the frame in position without the need for external support. Once the second frame 40 is attached, together with the platform 36, the extra 15 weight provides for further stability. The ceiling beam 70 and raised floor vertical edge 84 extend in a parallel relationship along the entire length of the opening 22 and so the first frame 38 may be moved to any position along the opening 22. The drive means is in the form of a driven roller 86 located adjacent the roller 78 of upright beam 44. The driven roller 86 20 abuts against the same vertical edge 84 of the raised floor surface 82 as disc 80. The roller 86 is mounted beneath the lowermost horizontal support beam 46, as is an associated drive motor 88 for rotating the roller 86 clockwise or anticlockwise. The skilled addressee would realise that because the roller 86 abuts with the fixed vertical surface 84 that any rotation of the roller 86 will cause the entire frame 38 to move. 25 The drive motor 88 is preferably an electro-pneumatic motor and includes pressurised air hoses 89 connected thereto. As mentioned, the walkway 26 is also height adjustable and the extent of adjustment can be seen in Figures 6a and 6b which respectively illustrate the lowermost and uppermost positions of the walkway 26. The second frame 40 is 30 vertically moveable with respect to the first frame 38, and once again the followir.g 11 description is in respect of one end of the apparatus only, but applies equally well to the opposed end. The vertical portion 60 of the upright beam 42 includes a vertical groove 9) on the its end side to receive two spaced apart rollers (not shown) associated with 5 connecting brackets 92 and 94. The connecting brackets 92 and 94 are fixed to the vertical component 52 of the L-shaped beam 48 at a spaced apart distance, as shown clearly in Figure 3. The brackets 90 and 92 are preferably welded to the L-shaped beam 48 at one end, and slideably attached at their opposed end to the vertical portion 60 by way of engagement between the rollers (not shown) and the groove 90. 10 Vertical adjustment of the L-shaped beams 48 and 50 relative to the first frame 38 is achieved using large pneumatic cylinders 96 and 98 which are mounted to the first frame 38 adjacent each of the upright members 42 and 44 respectively. The pneumatic cylinders may be supported against the horizontal support beams 46 of the first frame, or by any oilier suitable support means which can maintain the weight of 15 the L-shaped beams 48 and 50, and the platform 36. The pneumatic cylinders 96 and 98 house respective pistons 100 and 102 which are vertically -moveable by way of supply of pressurised air through connecting hoses 104. Further to brackets 92 and 94, the vertical component 52 of the L-shaped team 48 includes another bracket 106 fixed to the top of piston 100 of the pneumatic 20 cylinder 96 using a bolt connection 108. The same applies to L-shaped beam 50 and piston 102 of cylinder 98. Those skilled in the art would realise that in having the L shaped beams fixed to the pneumatic pistons, they and hence the platform 36 can be raised or lowered depending on whether the pistons are actuated to move upwards or downwards. The groove 90 and associated rollers (not shown) acts as a guide during 25 vertical movement of the L-shaped beams 48 and 40, as do the first frame rollers 64 and 78 during horizontal movement. Pressurised air hoses 110 associated with the pistons 96 and 98, and the hoses 89 associated with the drive motor 88, branch from a central air pressure distribuf on point (not shown) which draws pressurised air through a main hose 112. Pressurised 30 air is drawn from an external source such as an air compressor or pressurised air cylinders (not shown) and used to operate the pneumatic system. The pneumatic 12 system, in particular the way in which the hoses connect, is not described here in any more detail as it should be relatively well known in the art. The main hose 112, as well as any other fluid hoses that are required, is attached along a cable 114 traveling the length of the pit adjacent the ceiling beam 70. This is most clearly seen in Figire 5 1. The hose 112 is secured to the cable 114 using buckles (not shown) which are moveable along the cable 114 to allow for movement of the walkway 26. Those skilled in the art would realise that when the walkway 26 is located at one end of the pit 16, the hose 112 will be bundled together, and when at the other end of the pit 16, 10 the hose 112 will be extended along the cable 114 as shown in Figure 1. The walkway 26 therefore offers four different movements, horizontal movement in one direction along the opening 22, horizontal movement in the opposite direction along the opening 22, upward movement, and downward movement. Such movement is actuated by a person standing on the platform 36 who has access to Ibur 15 foot pedals 116, 118, 120 and 122 which are responsible for the four movements respectively. For example when pedal 120 is pressed, pressurised air will flow into the pneumatic cylinders 96 and 98 as required, and the walkway 26 will move downwards (unless it is already at its lowermost position), and so on. It is to be understood that the platform will move for as long as the foot pedal is pressed, and stop when 20 depressed so the position of the walkway is not limited to its uppermost or lowermost positions, but any position therebetween. The platform 36 includes various other features. The platform is a bucket--ype platform having a serrated metal upper surface 124 through which liquid and small bits of material may fall into an undercarriage 126. The undercarriage 126 is 25 optionally removable for cleaning. The platform 36 further includes safety rails 128 around its periphery, access doors 130, and an equipment tray 132 for supporting equipment 134 which is required to service the vehicle. It is to be understood that the platform 36 could include any other necessary equipment to carry out such services. Turning fmally now to Figure 8, there is shown a perspective view of the 30 opening 22 from inside the pit 16. Those skilled in the art would realise that when the walkway 26 has been adjusted to a desired position and a desired height, and service 13 on a vehicle has begun, personnel will require quick and easy access to tools and other equipment. For this reason, each opening includes one or more equipment stands 136 which are moveable along the length of the opening 22. The stand 136 comprises a central transverse beam 138 upon which tools and the like (not shown) may be placed, 5 and on the ends of the beam are downwardly extending shoulders 140 and 142 which extend into respective recesses 144 and 146 extending along beams 148 and 150 lining the opening 22. The recesses 144 and 146 slideably engage rollers 152 which are rotatably connected to each shoulder 140 and 142. Although not shown, the pit 16 also includes shelving around the periphery of the pit area 16 for carrying any 10 equipment that is necessary. The present invention therefore provides a pit-type vehicle service area 10 which overcomes various drawbacks with existing service areas of this kind. The service area 10 includes a walkway 26 within the pit 16 upon which skilled personnel stand to operate on the underside of a vehicle. The advantage of walkway 26 is that it 15 is moveable along the opening 22 of the pit 16 so that if two spaced apart areas of the vehicle need to be accessed, the user can simply actuate movement of the walkway to the desired area without the need to dismount the walkway or move all of their equipment. The walkway 26 is further height adjustable so that personnel can work at their preferred height relative to the vehicle. This is important because over long 20 periods, workers can develop serious back strain and muscle fatigue when working in undesirable positions. The service area further includes an oil sump (not shown) which is also moveable along the opening 22 in the same way as the equipment stand 136. The oil sump (not shown) can be moved along the opening 22 to an end of the pit 16 where it 25 may then be rotated so that oil therein is tipped into a large storage tank (not shown) located therebeneath for possible re-use. This is particularly useful when emptying a vehicle oil sump. The service area 10 includes other features which provide for a much cleaner and safer working environment than hitherto known service areas, including the 30 equipment stand 136 that is also moveable along the opening 22, the removable undercarriage 126 of the walkway 26, the air vents 30 for aerating the pit area 16, and shelving (not shown) around the periphery of the pit area 16. In the embodiment 14 shown, there is also quite a bit of space in the pit 16 between the two service areas defined by openings 22 and 24, and this area can be used to accommodate various electronic equipment and other machinery that may be required in servicing the vehicle. 5 Further advantages and improvements may very well be made to the present invention without deviating from its scope. Although the invention has been shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope and spirit of the invention, which is not to be limited to the details disclosed hereia but 10 is to be accorded the full scope of the claims so as to embrace any and all equivalent devices and apparatus. In any claims that follow and in the summary of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprising" is used in the sense of "including", i.e. the features specified nay 15 be associated with further features in various embodiments of the invention.

Claims (14)

1. A service walkway adapted for use in a service pit having a longitudinal opening for access to an underside of a vehicle, said walkway characterised 5 by: being elevated clear of the floor of the service pit; including a first frame mounted to a first side wall only of said service pit, said first frame being horizontally moveable along the length of the opening; and including a second frame which is vertically moveable relative to the first 10 frame.

2. A service walkway as in claim wherein said first frame includes two longitudinally spaced apart, upright beams having horizontal connecting beams, said upright beams including a lower diagonal component and an upper vertical component. 15

3. A service walkway as in claim 2 wherein at least one of said upright beams includes a drive means which when actuated causes said first frame to move horizontally.

4. A service walkway as in claim 3 wherein said drive means is in the form of a motor adapted to drive a roller which is rotatably mounted to the first frame, 20 said roller being positioned to contact a fixed vertical floor surface of the pit extending along the opening such that rotation of the roller causes said first frame to move relative to the fixed vertical floor surface.

5. A service walkway as in claim 4 wherein said motor is an electro-pneumatic motor capable of driving the roller in both clockwise and anticlockwise 25 motions and thereby provide for movement of the first frame in both directions along the opening.

6. A service walkway as in claim 4 or 6 wherein said first frame is supported at its upper end by a fixed vertical ceiling surface of the pit extending along the opening, said vertical surface being horizontally disposed from said vertical 30 floor surface towards said opening, such that the diagonal component of the 16 upright beams causes said first frame to lean against the ceiling surface whilst maintaining said vertical component in a vertical configuration.

7. A service walkway as in claim 6 wherein said upright beams include rotatable guide rollers which contact the ceiling and floor vertical surfaces. 5

8. A service walkway as in any one of claims I to 7 wherein said second frame includes two longitudinally spaced apart L-shaped beams having a horizontal component and a vertical component, wherein the horizontal component of the L-shaped beams extend transversely across said opening to support a service platform, said L-shaped beams also having horizontal connecting beams. 10

9. A service walkway as in claim 8 wherein the vertical component of the L shaped beams and the vertical component of the upright beams are equally spaced apart, parallel and slideably engaged.

10. A service walkway as in claim 8 or claim 9 wherein said L-shaped beams are connected to a second drive means fixed to the first frame, said L-shaped 15 beams being vertically moveable by way of actuation of said second drive means.

11. A service walkway as in claim 10 wherein said second drive means is in the form of two pneumatic cylinders which are fixed adjacent each upright beam of the first frame, said vertical component of each L-shaped beam being fixed 20 to corresponding pneumatic pistons.

12. A service walkway as in claim 1 wherein actuation of said pneumatic cylinders causes said pistons to raise or lower, thereby raising or lowering the L-shaped beams and platform.

13. A service walkway as in claim 12 wherein said platform includes a first, 25 second, third and fourth foot pedal, said first foot pedal used to actuate said drive motor to move said platform in one direction along the opening, said second foot pedal used to actuate said drive motor in the opposite direction along said opening, said third foot pedal used to actuate said pneumatic 17 cylinder and thereby raise said pistons, and said fourth foot pedal used to actuate said pneumatic cylinder and thereby lower said pistons.

14. A service area including a service walkway as defined in any of the claims 1 to 13. 5 18 This page intentionally blank