SE432225B - PNEUMATIC CONTROLLED HIGH AND LOWER DEVICE FOR TRUCK LIGHTS IN VEHICLES WITH AIR SPRING - Google Patents

Description

two parallel connected air valves 15 and 16, and through the connection 20 with a switching valve 17. In the shown switching positions with the switching valve 17 in neutral position 21, a control line 22 to the first relay valve 5 is through lines 23 and 24 in the switching valve 17 connected to a connection 25 in the second relay valve 6 via the connections 27 and 28 in the switching valve 17 and is connected to a connection in the air valve 15.

The schematically shown second relay valve 6 is designed such that the relay piston 30 is connected via a control inlet 26 to a control chamber 31, the stroke of the piston 30 ending with an outlet valve 33 with a vent 32 and opening the inlet valve 8.

A throttle valve 34, which in the form of a hole passes through the piston 30, provides a throttle connection between the control chamber 31 and its control inlet 26 and the chamber 9 or its connection 10 connected to the air bellows 11. In the symbolically shown relay valve 5 a corresponding throttle hole 35 is shown for the throttle connection between connections 22 and 12.

In the neutral position of the switching valve 17 the air valves 15 and 16, the alternating load of the vehicle and the consequent height adjustments of the body are affected, which by means of handrails or levers engage airing positions 36 or 37 or venting positions 38 or 39. l For coupling raising or lowering movements for example, when operating with swap bodies, the switching valve 17 outside the switching position 21 is "neutral" provided with a switching position 40 "Raise", 41 "Lower" and the two stop positions 42 and 43. For venting the system, the switching valve 17 is provided with one to the free conductive throttle valve 44.

A device as above operates as follows: If, in order to raise the platform, the switching valve 17 is switched from a neutral position 21 to the position 40, the connections 28 and 24 leading to the valves 15 and 16 in the switching valve 17 are blocked. In contrast, the supply connection 20 is connected to the connections 23 and 27, so that air can flow in through the throttle holes 35 and 34 to the bellows 13 and 11. Through the throttles, the pressure in the connections 22 and 26 and the associated control chamber 31 becomes higher than in the bellows, whereby the completed the displacement of the piston 30 closes the outlet valve 33 and opens the inlet valve 8 and the inlet connections 10 and 12 for unthrottled supply to the bellows 11 and 13 and allows a rapid air supply.

To lower the platform, the switching valve 17 is kept in position 41. Compressed air then flows from the bellows 11 and 13 through the throttling holes 34 and 35 and the switching valve 17 through the throttling hole 44 to the atmosphere.

Claims (3)

.8 (IÜTOTS 5 ~ 2 Thereby the pressure is lower in the control chamber 31, (eg at the relay 6) and the connections 22 and 26 to the relay valves 5 and 6 compared to the pressures in the bellows 11 and 13, so that these through the valves 5 and 6 can be quickly deaerated n The special speed can be changed by increasing or decreasing the diameter of the throttle hole 44. Patent claims: 1. Pneumatically controlled lifting and lowering devices for lorries for vehicles with air suspension, in particular for vehicles with swap bodies or semi-trailers, including air suspension bellows (11,13), which also serve as lifting and lowering devices for the flatbed, and whose and aeration takes place through air suspension valves (15,16), which are connected between a source of compressed air (2) and the bellows (11,13); and a sheet relief valve (17), which is connected between the air suspension valves (15, 16) and the bellows, and which has an additional inlet (20) connected to the compressed air source and a vent vent (44), characterized in in that it further comprises relay valves (5,6), which are connected between the compressed air source (2) and the air suspension bellows (11,13), and whose control inlets' (22,26) are connected to the connecting lines between the connecting valve (17) and the bellows, and suyp valves (34,35) are arranged in said connecting lines via their shaft closures to the control inputs and connections to the outlet of the relay valves (5,6), the suypwlercan of the throttle valves being so selected that when the connection valve is switched to connect its further input (ZOH -ill) the bellows, the pressure difference above the relay valves becomes large enough to switch them to release compressed air directly from the connected compressed air source (2, via inlet 3 and 4 respectively) to the bellows for the rapid venting, and that when the connection valve is employed to connect its venting outlet to the bellows, the relay valves of the then present pressure chamber are switched to a position for rapid venting. Lifting and lowering device according to Claim 1, characterized in that each relay valve (5, 6) consists of a relay piston (45) arranged in a housing and an inlet valve (8) arranged therein, which is adjustable by the piston. movements; a control sensor (31) arranged above the relay piston (45), which is actuated by the control sleeve (26); a first chamber (7) connected to an inlet from the compressed air source, located in the direction of the compressed air flow in front of the inlet valve (8), while a second channel (9) connected to the outlet connection (10) of the valve is located below the inlet valve. The raising and lowering device according to claim 2, characterized in that the throttle valve (34) is designed as a hole in the wall between the guide cam and the second cam (between 31, 9).