ES2277765B2 - METHOD FOR CONTROLLING PNEUMATIC SUSPENSION OF INDUSTRIAL VEHICLES AND CORRESPONDING DEVICE. - Google Patents

Abstract

Method for control of pneumatic suspension of industrial vehicles and corresponding device. It consists of a method and a device to keep the height of the platform of the vehicle in circulation constant, manual adjustment of the height of the platform in standstill, for leveling with the loading dock, limitation of its maximum height, automatic return based on driving height when the vehicle starts the march, which combines the said functions with the constant maintenance level with the loading dock, during loading or unloading, of any height value previously selected manually, regardless of the vehicle's loading status ; by means of two modules, one of leveling (7) and one of control (9), connected to each other and the first one also with the vehicle systems, uses a mechanical-pneumatic type technology. Of application in the manufacture of pneumatic suspension control devices of industrial vehicles.

Description

Pneumatic suspension control method of industrial vehicles and corresponding device.

The technical sector of this patent is the control of the suspension of industrial vehicles of which they are equipped with pneumatic suspension that uses pressurized air provided by the vehicle compressor to adjust the pressure in the diapreses that constitute the support of the platform of the vehicle on its wheel axles according to the different load values that can gravitate on said platform.

Indication of prior art

For a long time, they exist in the market several companies such as Wabco, Knorr-Bremse, or Haldex (formerly Grau), which market devices intended to perform, jointly or separately, the functions of keeping constant the platform height during vehicle movement by a leveling valve (A), and limiting the maximum height of the platform to protect the various organs from suspension of the vehicle using a height limiting valve (C).

These companies also market devices intended for manual adjustment of the height of the platform, with the vehicle stopped, to level it with the loading dock, by means of a command named here "manual raise-low" (B).

The device called is known "Tails", from Haldex (formerly Grau), intended for jointly perform manual height adjustment functions of the platform through a manual up-down control (B), and automatic system return (Function E) to position of circulation, as a security measure before the possibility that the driver forget to perform this operation manually, by an solenoid valve that is piloted by an electrical signal generated in the ABS brake device when the vehicle exceeds a certain speed.

Is known WO-A-91/06440 for height control for air suspension vehicles, such as a grouping system and connects to each other a series of independent valves, distributed in different parts of the vehicle or grouped some of them within the same drawer, to jointly perform the functions described above as A), B), C), and E). This system has the particularity of using a signal generated by the first service brake actuation to activate the function E) automatic return to the circulation position of the vehicle. If the mentioned signal is pneumatic, it is taken from the pneumatic circuit that drives the brakes. If said signal It is electric, it is taken from the electric circuit of the lights of Brake.

Control systems are also known. electronic suspension of Wabco companies and Knorr-Bremse. These systems are intended for jointly perform all the functions described as A), B), C), E), and, additionally, a function D) for self-leveling in loading dock with respect to any platform height value previously selected. These systems are based on the socket of data using electronic transducers, the interpretation of these data and the subsequent orders of action through a electronic control system based on a processor, for end up executing orders a block of solenoid valves simple.

The aforementioned self-leveling function D) in loading dock arises as a solution to a serious lack presented for all manual up-down systems mentioned before the electronic controls, since the height adjusted initially, to level the platform with the loading dock, is modified every time the value of the load on the vehicle, modification that occurs constantly during the loading / unloading process, which requires that height must be corrected manually on successive occasions.

The closest prior invention of which the Present invention part is known as EP 1084873 by method for control of pneumatic suspension of vehicles and module corresponding leveling, as a method and a device intended to perform the same functions A), B), C), D), and E) as Electronic suspension control systems of companies Wabco and Knorr-Bremse, but with the particularity of employ a mechanical-pneumatic technology. The main novelty of this invention lay in the fact of being able to perform the function D) of self-leveling in loading dock and not be based on an electronic control technology, through the use of a second leveling valve that can be coupled temporarily to the same height sensor used by the valve main grader (A), to automatically correct the height deviations that, during the loading / unloading process, occur with respect to the height initially set to align the platform with loading dock.

However, the EP method and device 1084873 has a serious deficiency due precisely to its main innovative feature of using a second valve bulldozer to perform the D) spring self-leveling function loading This is so why the operation of any valve bulldozer involves a variable supply of air flow compressed, from zero to the maximum value, depending on the degree of height deviation that occurs with respect to the neutral point or initial position. Thus, when the self-leveling function D) is executed at loading dock, air flow, feed or exhaust, which allows to recover the initially set height, will decrease substantially as the deviation is reduced and, in consequently, the self-leveling speed will be insufficient for the normal needs of the loading / unloading process of vehicle.

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The method and device proposed by the The present invention completely eliminates the problem explained for the method and device of EP 1084873. You can perform the same functions A), B), C), D) and E), and also uses means mechanical-tires but with a method different.

The main novelty of the method and device objects of the present invention, resides in the fact of being able to perform the function D) of self-leveling in loading dock and not be based on an electronic control technology, through the use of an intermediate arm or shaft that, thanks to a clutch pneumatic, can be temporarily attached to the same sensor arm height used by leveling valve A), to actuate alternatively two position sensors, mechanical-pneumatic, which respectively pilot two power distributors or air leakage from the suspension, so that the air flow of These distributors are always maximum and independent of the degree of deviation from the value of the height initially set for perform the self-leveling of the platform with the spring load.

The method and device objects of this invention is composed of two blocks that must be connected pneumatically with each other. A first block called here "Module Leveling "and a second block named here" Module command ". In this way, said system can perform all five functions already mentioned, using a technology mechanical-pneumatic

The present invention aims at a method and a device for controlling air suspension of vehicles, which performs each and every one of the following functions:

TO)

Constant maintenance of the height of the platform during the movement of the vehicle, by means of a leveling valve

B)

Manual adjustment of the height of the platform, with the vehicle stationary, to level it with the loading dock, using a sub-low control manual.

C)

Limitation of the maximum height at which the platform can be raised manually when using the "B" function, to protect the various organs of the vehicle suspension, by means of a height limiting valve; valve that can optionally be supported by two valves non-return and a quick exhaust valve, to perform a sub-function of rapid draining of the air from the suspension in certain types of vehicles.

D)

Constant level maintenance with the loading dock, during the entire loading or unloading process, of any platform height value that has been previously selected with the up-down function manual (B), regardless of the state of charge of the vehicle, by temporarily coupling an intermediate arm or shaft that alternately activates two position sensors, mechanical-tires, supported by other mechanisms specific.

AND)

Automatic return of the system to the function A) (traffic height) when the vehicle starts the gear and the driver has forgotten to make this return so manual, as a safety measure for its own organs vehicle and the entire road environment, using a solenoid valve which is piloted by an electrical signal generated when a certain optional control parameter (e.g. first brake actuation, detected in the electrical circuit of the corresponding lights; or when exceeding a certain travel speed, taking the ABS measurement of the vehicle, etc...).

In order to make clearer the explanation that will follow, is accompanied by twelve sheets of drawings that in fourteen Figures represent the essence of the present invention.

Figure 1 shows an installation scheme of the corresponding system modules in a semi-trailer equipped with three wheel axles and six suspension diapreses pneumatics.

Figure 2 shows the complete scheme of method operation.

Figure 3 shows a complete scheme implemented by the elements that give rise to the sub-function of rapid draining of the air from the suspension, described as optional before.

Figure 4 shows a side view of a material realization of the "leveling module" of system.

Figure 5 shows a top view of the same material embodiment of figure 4.

Figure 6 shows a sectional view of the leveling module according to A-A 'in figure 4.

Figure 7 shows a sectional view of the Leveling module according to B-B 'in figure 5.

Figure 8 shows a sectional view of the leveling module according to C-C 'in figure 5.

Figure 9 shows the representation simplified of some elements of figure 7.

Figure 10 shows a sectional view of the leveling module according to D-D 'of figure 4.

Figure 11 shows the complete scheme of pneumatic connections between the different elements of the module leveling, based on figures 6, 8, and 10 listed previously.

Figure 12 shows a top view of a material realization of the system control module.

Figure 13 shows a sectional view of the control module according to E-E 'in figure 12.

Figure 14 shows a sectional view of the control module according to F-F 'in figure 12.

In these figures indicated indicated by:

one

air tank for suspension

2

line air suspension right

3

line air suspension left

4A

right diapreses of suspension

4B

left diapreses of suspension

5

wheels vehicle

6

axes of the wheels

all of them forming part of the basic installation of any vehicle with suspension pneumatics.

The elements referred to below form a specific part of the suspension control method of industrial vehicles and material realization of the device corresponding that occupy this description, and indicated with

7

he leveling module that occupies this description

8

he height sensor arm leveling module

9

he control module that occupies this description

10

the multi-connection pipe between both modules

eleven

feed check valve or entry

12

leveling valve

13

height limiting valve

14

clutch device tire

fifteen

he intermediate arm or shaft that can engage the clutch

16

he compensating device for excess displacement

17

power sensor

18

exhaust sensor

19

circuit selector valve for feeding

twenty

circuit selector valve for escape

twenty-one

pneumatic distributor of feeding

22

pneumatic distributor of escape

2. 3

mode selector valve leveling

24

quick exhaust valve optional

25

check valves for the system optional quick exhaust

26

sub-device, of the joystick, for manual activation of the microvalves supply and exhaust pilot

27

pilot microvalve for manual operation of the exhaust manifold (position IIB)

28

device for guiding the joystick.

29

non-return valves

30

pilot microvalve for the manual operation of the clutch device (position III)

31

drum with cams, lever control, for manual operation of the pilot microvalves of the clutch and the mode selection valve leveling

32

Joystick with five possible positions

33

automatic return cylinder a position I

3. 4

pilot microvalve for the actuation of the leveling mode selector valve (position II and III)

35

pilot microvalve for the manual operation of the power distributor (position IIA)

36

solenoid valve for automatic return to position I

37

electrical connection for solenoid valve

38

auxiliary rod

39

joint rods

40

main rod

41

rod nut

42

screw rod

43

screw anchor housing clutch

44

distributor body

Four. Five

screw anchor body dealers

46

anchor bolt leveling module a vehicle platform

47

connection record port P1

48

connection connections port P21

49

connection connections port P22

fifty

base Multiple connection for ports C-1,2,3,4 and 5

51

main body of the module leveling

52

clutch housing

53

self-lubricated bearing

54

retainer of fat

55

meeting toric

56

semi-axis I

57

semi-axis II

58

screw

59

clutch cylinder

60

ball rolling

61

clutch piston

62

meeting toric

63

meeting toric

64

clutch spring

65

clutch closure

66

retaining ring

67

disk clutch

68

clutch disc holder

69

ball rolling

70

Barrette

71

semi-clamp I

72

torsion spring

73

semi-clamp II

74

meeting toric

75

self-lubricated bearing

76

sensor stem

77

meeting toric

78

retaining ring

79

sensor body

80

sensor spring

81

meeting toric

82

clapet sensor

83

meeting toric

84

clapet dock

85

meeting toric

86

screw adjustment sensor

87

retaining ring

88

sensor closure

89

fastening nut

90

exhaust leveling valve

91

main exhaust

92

top rear

93

meeting toric

94

height cut sensor

95

butt cap

96

cut-off stem

97

meeting toric

98

piston-clapet cut height

99

dock

100

height cut regulation

101

top Cut valve

102

o-ring

103

retaining ring

104

o-ring

105

retaining ring

106

o-ring

107

top leveling valve

108

clapet dock

109

clapet leveling valve

110

contact rod

111

o-ring

112

seal closure

113

retaining ring

114

leveling valve spring

115

contact bushing

116

clutch power supply

117

tube clutch feed

118

sliding leveling valve

119

top

120

retaining ring

121

o-ring

122

o-ring

123

dock

124

sliding distributor

125

o-ring

126

retaining ring

127

final separator

128

distributors board

129

gasket separator

130

top

131

sliding distributor

132

special separator

133

back closure

134

o-ring

135

dock

136

control module body

137

drum drive

138

drive lever

139

axis

140

support ring

141

top

142

o-ring

143

retaining ring

144

distributor sensor

145

o-ring

146

washer

147

distributor body

148

dock

149

o-ring

150

clapet distributor

151

dock

152

o-ring

153

distributor closure

154

retaining ring

155

reset cylinder body

156

centering

157

reset piston

158

dock

159

o-ring

160

ball positioner

161

dock

162

positioner closure

163

knob lever

164

smock

165

Anchor plate

166

anchor bolt

167

exhaust control module

Then, according to figures 1 and 2, Describe the connection of this control method:

Leaving aside the different possibilities of combine the escape routes of the different elements that form, the leveling module 7 has eight ports of communication with the outside Three of these ports P1, P21 and P22, communicate with vehicle elements:

with P1 the power supply is signaled from the suspension air tank 1; with P21 and P22, the air outlets to control respectively the lines of the suspension 2 and 3.

The remaining five ports C1, C2, C3, C4, and C5 communicate directly with their homonyms in the command module 9.

The control module 9 has five ports of communication with the outside: C1, C2, C3, C4 and C5, which communicate directly with their homonyms in the leveling module 7.

Explanation of an embodiment

The leveling module 7, according to figure 1, is fixed to the vehicle platform, approximately in the line of its longitudinal axis and above the wheel axle 6 which It is intended to be used to anchor the height sensor arm 8 of the system. Said sensor arm 8 is a moving part of the module leveling 7, and its displacements are proportional to the vertical height variations between the vehicle platform and its wheel axle 6, identical variation to that produced between the platform and ground, while the wheels of the vehicle are find on it.

The Command Module 9, according to figure 1, is preferably fixed on one side of the back of the vehicle platform, to give easy access to its handling by the driver in the vicinity of the loading dock.

The five different ways of communication pneumatics between both modules can be realized by means of a only pipe 10 that internally has the five tubes of air needed Said pipe 10 would have a system of fast and multiple connection at its two ends to establish the communication between both modules.

System operation A) Leveling of the vehicle in circulation

When the vehicle is built it is preset a height of circulation, corresponding to a certain fixing position between the height sensor arm 8 and the axis of reference wheels 6, at which point, according to figure 2, the main leveling valve 12 is in its central position neutral That is, with all its tracks closed: neither enters nor leaves air from the suspension lines through ports P21 and P22

When the joystick 32 is in its position I, lever to the left, the function of leveling of the vehicle in circulation. In that position, the micro valve 34 is not activated, staying connected to exhaust the C5 line of pilot mode selector valve leveling 23, so the two ports of communication with the suspension P21, P22 are connected to the respective lines of leveling valve output 12. When increasing the load on the platform, the suspension diapreses 4A, 4B are seen compressed, reducing the height between the platform and the ground. This causes the elevation of the sensor arm 8 with respect to its own leveling module 7, changing the position of the valve bulldozer 12 to give way to compressed air that, coming from the supply port P1 and through the selector valve of the leveling mode 23, is introduced into the suspension lines through ports P21 and P22, increasing the pressure of the diapreses 4A, 4B and causing the platform to rise its initial position, since simultaneously the sensor arm 8 has moved the leveling valve 12 back to its central position neutral, when the air inlet stops at the lines of the suspension. If the load is reduced, the process that is triggers is exactly the opposite of the one already described: Initially would increase the height of the platform, which would compensate for the main leveling valve 12 drawing air from the lines of the suspension, through ports P21 and P22, to decrease its pressure and lower the platform to its initial height.

B) Manual up-down function

The vehicle is stopped with its rear next to the loading dock and you want to manually level the height of the platform of the vehicle at the height of the dock, to be able to carry out the loading or unloading of merchandise. For this and according to the Figure 2, the driver must first turn the lever command 32 until its interlocking occurs in position II, position called "stop". In this position and thanks to drum cam profile 31 of joystick 32, remains operated the microvalve 34 to feed the air from C2, to the pilot control valve C5 line of leveling mode 23, so ports P21 and P22, of communication with the suspension lines, leave your connection with leveling valve 12 to be now connected to the pneumatic distributors of feed 21 and exhaust 22.

Thanks to the guidance device 28, the position II of the joystick 32 is the only one from which it can be displaced vertically as we can see in figure 2; for, through its link with the sub-device 26, to be able to keep the microvalves operated alternately 27 or 35. For the operation of said microvalves to result effective, lever 32 must be manually operated on positions IIA or IIB; since, when released, lever 32 automatically returns to position II thanks to the effect of springs of the microvalves themselves 27 or 35.

When the driver wants to manually raise the vehicle platform, you must keep lever 32 in the position IIA, to operate the microvalve 35 which, by means of the line C4 and through circuit selector valve 19, performs the pilot of the power distributor 21 which, through the leveling mode selector valve 23 and ports P21 and P22, introduces air into the suspension lines, increasing the pressure in the suspension diapreses 4A, 4B and causing the platform lift. When the driver considers the platform has reached the required height, just release the joystick 32 to return to position II and cease the air inlet to the suspension. When the driver wants to get off manually the platform, you must keep in position IIB the lever 32, to operate the microvalve 27 which, through the line C3 and through the circuit selector valve 20, performs the pilot of the exhaust manifold 22 to connect the exhaust air from the suspension, lowering the pressure in the 4A diapreses, 4B and causing the descent of the platform, which ends when the  driver releases lever 32 so that it returns automatically to position II.

It should be noted that the selector valve of power circuit 19 can receive two pilot signals different to drive the pneumatic feed distributor 21. One of the signals, as we have just seen, from the micro valve 35 manually operated and the other signal, as we will see more forward, from the microvalve-sensor 17 of power in automatic mode; with the peculiarity of not leaving escape the air from one of the signals through the circuit of Alternative signal input. The same goes for the valve circuit selector for exhaust 20 with respect to the elements Exhaust control

Before restarting, the driver you must turn the operating lever 32 to position I. this way, ports P21 and P22, of communication with the lines suspension, lose their connection with distributors feed 21 and exhaust 22 tires, to restore it with the leveling valve 12, which returns the platform to the leveling function of the vehicle in circulation.

C) Height limitation function with additional and optional quick emptying sub-function air suspension

The height limiting valve 13 is the device responsible for limiting the maximum height to which you can manually lift the platform when using the function "B", avoiding the damage that could be caused to the elements of the suspension of the vehicle if said height were exceeded.

When operating lever 32 of control module 9 to cause manual lifting of the platform, as explained in B) and observing figure 2, the pneumatic distributor supply 21 introduces air into the suspension lines which, coming from the P1 supply, crosses the valve height limiter 13. With the platform lift, the sensor arm 8 descends, to a predefined point where forces to change position to the height limiting valve 13. First change of position in which the three tracks are blocked of said valve, cutting off the air passage to the lines of the suspension 2 and 3, through ports P21 and P22, and stopping the platform elevation at the maximum predefined height.

Figure 3 is the result of adding, to the Figure 2 scheme, some elements that allow to perform the function optional explained below. The limiting valve of height 13, optional quick exhaust valve 24, and both 25 non-return valves optional, jointly perform the sub-function of rapid draining of the air from the suspension, to protect against sudden rises of the platform that occur in the unitary unloading of goods very heavy elevations that cannot be annulled by the performance of the leveling valve 12, with the control in position I of circulation, due to its limited exhaust flow. This situation it would be even worse with the command in position II of "stop", since neither air in or out of the suspension. This situation would only be compensated, in most cases, by position III of the command, which has not yet been explained. The reason why the fast emptying sub-function has character optional, is in the fact that it is not usually necessary for the Most vehicles

According to figure 3, the two non-return valves 25 are interposed between communication ports P21 and P22 with suspension lines, and quick exhaust valve 24, whose pilot line is common with the line that carries the air to the pneumatic feed distributor 21, after crossing the height limiting valve 13, from the feeding port P1. If the height limiting valve 13 has not yet entered action, the pressure in the pilot valve of the exhaust valve fast 24 is higher than the suspension pressure at ports P21 and P22, so that check valves 25 will remain closed. When the unloading of a very heavy merchandise or of a set of them that are also, the diapreses of suspension 4A, 4B are sharply decompressed, beginning the platform to rise very quickly and forcing the valve height limiter 13 to make two position changes consecutive until reaching the third and last of them, remaining connected to exhaust the pilot line to the quick exhaust valve 24. At that time, the suspension pressure itself, through P21 and P22, will open the two non-return valves 25, becoming these in high-flow exhaust routes for excess air in the suspension, which will go into the atmosphere through the valve quick escape 24. In this way, you can stop or reduce the abrupt elevation of the platform and prevent harmful effects This could cause the suspension.

Once the platform lift is stopped, it will begin to descend rapidly until the valve limiter 13 reach its initial position and have pressure again the pilot of the quick exhaust valve 24, at which time The quick emptying of the air from the suspension ends.

D) Spring self-leveling of load

This function arises as a solution to a serious lack presented by all systems up-down existing manuals in the market, since the height selected to level the platform with the spring it changes each time the value of the load on the vehicle does, variation that occurs constantly during the process of loading / unloading, which requires that said height must be corrected manually on successive occasions.

The main novelty presented here, resides in the self-leveling function in loading dock, which achieves keep the selected height constant, despite variations of load that occur on the vehicle. After adjusting manually platform height, using IIA functions or IIB of the control module 9, according to figure 2, the driver must turn the control lever 32 until it reaches its interlock in the position III, when the activation of the latter is established function. Microvalve 34 remains actuated, as already was in position II, to keep active the piloting of the leveling mode selector valve 23. The novelty of the position III is the actuation of the microvalve 30, by a cam in the drum 31 of the lever 32, to activate, through of line C1, the pilot of the pneumatic clutch device 14. Activation of clutch device 14 establishes the joint temporary mechanics between the arm or intermediate shaft 15 and the arm height sensor 8 from the self-leveling height that has been selected The power sensor 17 and the exhaust sensor 18 they are microvalves, mechanically operated, held in position resting until that time, which may alternatively be triggered by height variations, in one way or another, transmitted by the sensor arm 8 and its temporary union with the arm intermediate 15, through the excess compensating device displacement 16. During actuation of sensors 17 or 18, the compensating device 16 will remain rigid until the sensors 17 or 18 reach their limited maximum travel. From this point, the additional displacement of the sensor arm 8 will be assumed by the deformation of the compensating device 16.

When, after selecting position III of the control module 9, the load on the platform of the vehicle, the descent of this occurs by the compression of the suspension diapreses 4A and 4B, so that the sensor arm 8 is elevates with respect to the leveling module 7 itself; movement that causes the power sensor 17 to operate carry out, through circuit selector valve 19, the pilot of the pneumatic power distributor 21 which, to through the leveling mode selector valve 23 and the ports P21 and P22, is responsible for introducing air into the suspension, to increase the pressure of the diapreses 4A, 4B and cause platform lift to selected height initially; height at which the power sensor 17 has ceased to be activated and ceases its piloting to the distributor of power 21. If the load on the platform is reduced, the The process that is triggered is the inverse of the one already described: initially it would increase the height of the platform, activating the exhaust sensor 18 to pilot the pneumatic distributor of Exhaust 22 and extract air from the suspension, lowering the pressure on diapreses 4A, 4B and lowering the platform to the initially selected height.

Returning the joystick to the position II, the microvalve 30 ceases to be activated and puts out, at via line C1, the clutch device pilot 14, ending the self-leveling function in loading dock.

E) "Reset" or restore function

It could happen that the vehicle starts running and the driver has forgotten to return the joystick 32 to the position I of vehicle circulation, being found in the position II or position III. This could pose serious problems with the stability of the vehicle and / or damage to the drive on low steps and be raised Regarding your normal position.

To prevent this eventuality, the function "reset" or restore returns command 32 to its position I, automatically, at the moment the march starts by activating a reference parameter. Saying parameter activates solenoid valve 36, according to figure 2, through of an electrical signal taken at electrical connection 37. Said electrical signal changes position to solenoid valve 36, establishing communication between the C2 air supply and the return cylinder 33, which pushes and moves the joystick 32, if not already, until position I.

The activation of the electrical signal of reference, which starts this function, will depend on the parameter of reference that is intended to be used. It may be the connection with the electric circuit of the vehicle's brake lights, which would activate the "reset" function with the first brake operation, or the interconnection with the control module of the A.B.S. or E.B.S. of the vehicle, which would activate it when the vehicle reach a certain circulation speed, or with any another reference parameter that may represent the beginning of the vehicle running.

Description of a material embodiment of the leveling module 7.

Figures 4 and 5 represent two views exteriors of the proposed material realization for the module leveling 7. Main body 51 and distributor body 44, of the leveling module 7, are defined as aluminum blocks extruded, of rectangular section, where the housings for different devices, connections internal between said devices, the connections between both blocks, communication ports with the outside, and threads for the different anchor bolts. The union between the bodies 51 and 44, using screws 45, defines a face common to both blocks, in which the housing of the joints have been mechanized that give the necessary tightness to the communication conduits direct through said joining face. Clutch housing 52 is attached to the main body 51 by means of screws 43 and, In addition to containing various leveling module devices 7, serves as an input element for the height sensor arm 8.

According to section A-A 'of the Figure 4, Figure 6 shows the constructive details of the leveling valve 12, the height limiting valve or cut 13, and the system for actuating both valves using 56.57 semi-axes as arm parts height sensor 8. In addition, the system of air supply for pneumatic clutch drive 14.

According to section B-B 'of the Figure 5, Figure 7 shows the construction details of the coupling and drive devices to perform the self-leveling function on loading dock: pneumatic clutch 14, intermediate arm or shaft 15, and excess compensating device displacement 16.

According to section C-C 'of the Figure 5, Figure 8 shows the construction details of the power sensors 17 and exhaust 18, for the function of self-leveling in loading dock, and how they are directly powered.

According to section D-D 'of the Figure 4, Figure 10 shows the construction details of pneumatic supply 21 and exhaust 22 distributors, and of the leveling mode selector valve 23, all of them within the distributor body 44.

Figure 11 shows the complete scheme of the pneumatic connections between the different elements that configure the present material embodiment of the module leveling 7.

Although they have not been represented, it should be indicated that circuit selector valves 19, 20 are located housed on the same face as the power sensors 17 and Exhaust 18. The same applies to the non-return valve feed 11, housed, according to figure 5, on the same face of the main body 51 than the record 47, which it supports.

After machining, on the faces of bodies 44 and 51, the drills made to achieve internal connection are open. Drills that do not represent communication with the outside, or between the common face of both bodies, are plugged by stainless steel balls introduced with press. The communication ports with the outside P1, P21 and P22 are constituted by threaded holes to install respectively the quick plug connectors 47, 48 and 49, where the corresponding pipes will be connected. The exhaust ports of the different devices communicate with the "leveling valve exhaust" 90 and "main exhaust" 91 outputs, which can be seen in Figure 4. According to Figures 5 and 11, ports C1, C2, C3, C4 and C5, for the connection with their homonyms in the control module 9, are grouped in the multiple connection base 50, where the corresponding connector of a single politubo hose 10 is coupled, which allows five independent conduits, simultaneously
snapshot.

About the material realization of the module leveling 7, it is important to note that the generic function of each one of the individual devices and the interactions between they, through internal connections, to achieve different functions are exactly equivalent to those described previously, in the explanation of the method, according to figures 2 and 3. For this reason, these explanations will not be repeated and, at From here, the descriptions will aim at identification between the generic functions of each device of the method and material form in which this is achieved by Proposed material realization (parts, dispositions, etc ...).

Description of the material embodiment of the arm height sensor 8.

According to figures 4 and 5, the height sensing arm 8 is basically constituted by the main rod 40 and by the semi-axes 56 and 57. The auxiliary rod 38, articulated at both ends, transmits vertical displacements (variations in the height of the platform) to the main rod 40, in which rotational movements occur jointly with the semi-axes 56 and 57, who are responsible for operating the corresponding devices
internal

According to Figure 6, it should be noted that both semi-axes 56 and 57 are linked together, of rigid shape, using screws 58, to rotate as if One piece will be. The reason to use initially two pieces is in the constructive need to be able to introduce and mount on them another series of mechanisms.

Description of the material embodiment of the leveling valve 12.

The constructive details of the valve bulldozer 12 are part of the known technique, so only A basic description is going to be made.

According to Figure 6, the left end of the semi-axis I (56) has a protuberance cylindrical and eccentric to the semi-axis itself, on the which is mounted the contact bushing 115, to be introduced in the front groove of the slide 118 of the leveling valve 12. In this way, the rotating movement of semi-axis I (56) may act vertically, in one or another way, to the leveling valve 12. The initial position neutral leveling valve is determined by the closure simultaneous, admission and escapement, which clapet 109 performs with the lower part of your accommodation, thanks to being pushed by the supply pressure in said housing and by the spring 108, and with the exhaust hole that passes through the contact rod 110, solidarity with the slide 118; communication channels that can be more easily identified if the figure is also observed eleven.

When, from the neutral position, the stem of contact 110 moves up and separates clapet 109 from its lower seat, the two-way power is established leveling valve outlet 12. When said stem of contact 110 moves down and loses contact with the clapet 109, its own internal exhaust duct is open, at that the two outlet ways of the valve are connected bulldozer 12.

Description of the material embodiment of the height limiting valve or shut-off valve 13.

According to figures 6 and 11, it is observed that the cutting sensor 94 can be moved vertically upwards by turning the cam profile, located just below it, with the which counts the semi-axis I (56).

The piston-clapet 98 is maintained in contact, due to spring 99 and chamber pressure upper feed, against the bottom of your housing, so the escape route of this device. The normal passage of air, towards the lower chamber, is produces through the central hole of the clamp-piston 98; until that step is closed by the cutting rod 96, which has been raised in solidarity with the sensor of cut 94, at the moment the preset value is reached for the maximum height at which the platform can be raised. That height  It can be adjusted by turning the cutting regulator 100, for threading or unscrewing the cutting rod 96 relative to the sensor of cut 94, which determines the initial closing distance between said cutting rod 96 and piston-clapet 98.

When, after establishing the closing contact, the cutting rod 96 continues to raise the piston-clapet 98, the exhaust connection is established of the outlet path of the height limiting valve 13, so that it would be feasible to activate an additional escape sub-function fast air suspension, exposed as optional during the Method explanation

Description of the material realization of the pneumatic distributors of feed 21 and exhaust 22, and of the leveling mode selector valve 23.

According to figure 10, it can be seen that the pneumatic distributors of feed 21 and exhaust 22 They have the same construction. Both are distributors of sliding, two-way and two positions, operated by pneumatic and spring return piloting. The selector valve of leveling mode 23 is a pneumatic distributor of Sliding, five-way and two positions, with pneumatic piloting and spring return.

The operation of these three distributors It is based on the internal arrangement of several cameras, isolated and separated by joints 128 and spacers 129 and 132, which correspond to the different communication channels of the distributor, to be able to establish different connections between they according to the different positions that, alternatively, they can occupy the existing slots on the slides 124 or 132. In figure 11 the different ways of communication of these distributors according to the pneumatic scheme  Complete leveling module 7.

Description of the material realization of clutch device 14, of the intermediate arm or shaft 15, and of the compensating device for excess displacement 16.

According to figure 7, the different pieces, of the material realization, that integrate the clutch device 14, intermediate arm or shaft 15, and the compensating device for excess displacement 16; all they are housed inside the clutch housing 52 and mounted on the complete shaft resulting from the joint solidarity of the two semi-axes 56 and 57 of the sensor arm of height 8.

The clutch device 14 is based on a friction clutch, pneumatically operated, with the mission of temporarily coupled to semi-axes 56 and 57, to through intermediate shaft 15 and compensating device 16, to be able to activate sensors 17 or 18 alternately during activation of position III of control module 9, allowing that the function D) of spring self-leveling of load.

According to figures 6, 7 and 8, the cylinder of clutch 59 has three appendices that are located in housings specific within the main body 51. The two appendices sides serve to actuate, alternatively, the power sensors 17 or exhaust 18 during the activation of the clutch device 14; and, also they serve, so that said clutch device 14 remains in its static position initial, by contact with sensors 17 and 18, and independent of the movement of semi-axes 56 and 57, when not It is activated. The third appendix, of the clutch cylinder 59, serves as a support for the record 116, where the tube 117 is connected which is configured as an intermediate and flexible route for air supply, from the fixed feeding path of the body main 51, of the clutch device 14. The flexibility of the tube 117 allows the clutch device 14 to be fed despite the small rotational movements that it should perform during operation.

According to figure 7, the clutch cylinder 59 It has a series of longitudinal grooves on its diameter outside, where the corresponding ones are embedded clutch piston guide appendages 61, so that said piston 61 can move axially inside cylinder 59, but cannot rotate with respect to 61. Clutch seal 65, although not have to move axially, take advantage of the same system as the piston 61 to be forced to rotate jointly with the clutch cylinder 59. The pins 70, of the intermediate arm 15, are located in individual holes of the clutch disc holder 68, to prevent it from moving axially with respect to the semi-axis I (56) but can rotate with respect to 61, thanks to the bottom of said pins 70 being located inside a groove of the semi-axis I (56).

When the device performance is ordered clutch 14, pressing its pneumatic chamber under pressure, is produced displacement of clutch piston 61 in the direction of clutch closure 65, against the effort of spring 64, which maintained to these two initially separated pieces, and against the effort of retaining ring 66, which prevents axial displacement of the closure clutch 65 with respect to clutch cylinder 59. As a result of said displacement, the friction disk 67 and the contact area of the clutch disc holder 68 will be trapped between the piston clutch 61 and clutch closure 65. The axial effort made, in combination with the high coefficient of friction of disk 67, allows the generation of high torque values relative between clutch device 14 and intermediate shaft 15, which determines that these two elements are bound to turn in solidarity for the duration of device activation  clutch 14.

In order to help sensors 17 and 18 in his additional mission of maintaining his initial position at clutch device 14, when it is deactivated, friction efforts that the movement of the semi-axis I (56) generates on its support with the clutch cylinder 59, since said cylinder 59 has been mounted on two rows of 60 balls, housed in two slots of the semi-axis I (56), so that the relative rotation between These two elements involve rolling and not sliding. This same operation has been performed with intermediate shaft 15 and with semi-clamps 71 and 73, of the device compensator 16, to minimize parasitic friction stresses among them.

For the "D" function of self-leveling in loading dock, be performed in an effective and precise way, it is necessary that the activation of sensors 17 and 18 be performed as a result of small variations in the height of the platform. For this reason and according Figure 8, the angle that the clutch cylinder 59 must rotate to activate the sensors of the two lateral appendages supply 17 or exhaust 18, is very small. However, if the variation of the load on the vehicle has been very large, the "D" function will need a period of time to reset the height initially set, so, after the activation of the corresponding sensor 17 or 18, the semi-axes 56 and 57, of the height sensor arm 8, they can continue their movement until they reach a turning angle much older. To compensate and make this difference compatible in the angular displacement, the leveling module 7 has a compensating device for excess displacement 16, which can see figures 7 and 9.

According to figure 9, a simplified representation, with respect to figure 7, of the pieces comprising the compensating device for excess of displacement 16 and other parts of the system with which this  device is directly related, in order to do more Easy explanation of its operation.

According to figures 7 and 9, the device compensator 16 is composed of semi-clamp I (71), the semi-clamp II (73), and the torsion spring 72. The area with the largest diameter of the semi-clamp I (71) is mounted and supported on a row of balls 69 of the clutch disc holder 68; and, on the other hand, it incorporates a drive appendix, which also serves as a connecting element with the cylindrical area of smaller diameter, located next to the semi-axis II (57), to allow support on a row of balls 60 of semi-axis I (56). The area of larger diameter of the semi-clamp II (73) is supported on a row of balls 69 of the semi-axis II (57); and, on the opposite side, incorporates an appendix of drive, which links to the area of smaller diameter to support on a row of balls 60 of the semi-axis I (56) and It is located next to the clutch disc holder 68.

According to Figure 9, the torsion spring 72 must be pre-tensioned before anchoring the hinges of its two ends in the corresponding housings on semi-clamps 71 and 73, so that the torque, generated by spring 72, push each semi-clamp 71 and 73 according to rotation directions opposites, so that, in the intermediate space to their respective drive appendages, can keep pressed and aligned to two other central appendages, shorter, that are part of the semi-axis II (57) and of the clutch disc support 68. Thus, the operation of the compensating device 16 can be assimilated to that of a kind of rotary clamp, which allows the clutch disc support 68 in solidarity with the semi-axes 56 and 57, until the moment the sturdy effort offered by bracket 68 outperform the effort of torsion spring pre-tension 73, so the support 68 may remain stopped while the semi-axes 56 and 57 continue their movement rotary.

According to figure 7, at the moment when activate the "D" function, self-leveling in loading dock, clutch device 14 is operated, to be coupled with intermediate shaft 15 which, through the compensating device 16, it is also with respect to semi-axes 56 and 57 of the height sensor arm 8. Al a variation of load on the vehicle platform, the corresponding variation in height causes the rotation of the semi-axes 56 and 57, so that, according to figure 8, the side appendages of clutch cylinder 59 of the device clutch 14, make the alternative sensor drive effective supply 17 or the exhaust sensor 18 and start the process to restore the initial height of the platform, since the effort required for this drive is less than pretensioning force of the spring 72 of the compensating device 16. However, after this drive, the clutch device 14 you can continue turning a little more, until one of your appendices lateral contact with the surface of your housing within the main body 51. From that point, the clutch device 14, together with intermediate arm 15, are unable to continue turning in the same direction of rotation However, according to figures 7 and 9, the semi-axes 56 and 57 if they can continue doing so, since the rotation of the appendix of the semi-axis II (57) will displace the appendix of the semi-clamp I (71) or that of the semi-clamp II (73), turning them against the torsional deformation of the spring 72 once its effort of pre-tension while the intermediate shaft 15 remains locked by its union with the clutch device 14.

When it starts to reset, so effective, the height initially set for the platform, is triggers the exact opposite process to the one explained, which It ends when, once the initial height is restored, the clutch device appendices 14 have also resumed their initial position and the actuation of the sensors 17 or ceases 18.

It should be noted that, in the material embodiment of these devices, the sequence in the device location of clutch 14, intermediate arm 15, and device compensator 16, with respect to the height sensor arm 8 and the sensors 17 and 18, it is inverted if we compare it with the proposal in the method according to figure 2. However, the process triggered and the results obtained are exactly the same.

Description of the material realization of the power sensors 17 and exhaust 18.

According to Figure 8, it can be seen that the pneumatic power and exhaust sensors 18 have 18 The same construction. Both are small clapet distributors, three-way and two positions, mechanically operated and with spring return, of the type that is commonly used to pilot other major distributors after Detect the mechanical contact of a mobile device. Be they are housed inside the main body 51, so symmetrical with respect to clutch device 14, in order to be actuated, alternatively, by the two lateral appendages of clutch cylinder 59, and, accordingly, perform pilot of power distributors 21 or exhaust 22 during the execution of the "D" function, self-leveling in loading dock

According to figure 11, the communication paths of sensors 17 and 18 within the circuit complete tire of the material embodiment of the module leveling 7. According to figure 8, when sensors 17 and 18 do not are operated, clapet 82 is pressed against its upper seat due to spring 84 and existing pressure in the lower feed chamber, to which it maintains incommunicado regarding the upper chamber of service or exit. He inner hollow and upper holes of sensor rod 76 they represent the escape route of this distributor, with which the upper chamber of service is communicated when it does not exist a closing contact between the lower end of the sensor rod 76 and clapet 82. At the moment one of the appendices of the clutch cylinder 59 run sensor rod drive 76, of sensor 17 or 18, said sensor rod 76 will be displaced down against the effort of spring 80, to contact and also move clapet 82, so the escape route will remain closed and the pilot exit path (upper chamber) will remain connected to the lower feed chamber through the seat that the clapet 82 has left open.

In order that the "D" function of self-leveling in loading dock, can be performed with the greatest promptness and accuracy possible, sensors 17 and 18 have been configured with great sensitivity to make changes from escape to food or vice versa, which implies a very low drive travel. By what is characteristic is effective, it is also necessary that, after assembly, the two sensor rods 76, of the sensors 17 and 18, are keep in simultaneous contact with the respective appendices of the clutch cylinder 59, eliminating or minimizing possible gaps in said contact, so that they do not imply an increase in the drive path. If we consider the tolerances of manufacture of the large number of elements involved in the achievement of adequate final relative positioning, said precision would be very difficult or impossible to achieve when mentioned devices have a single position of mounting.

To solve this eventuality, the sensors 17 and 18 have the possibility of being adjusted vertically, after assembly, to minimize the clearances of your drive According to figure 8, after mounting the sensors 17  and 18, the sensor closure 88 must be tightened and fixed in its accommodation. However, the rest of the elements that configure the mentioned sensors, are housed inside the body sensor 79, which can be displaced vertically by the threaded or unscrewed the adjustment screw 86 with respect to the closure 88, until the simultaneous contact of the two sensor stems is achieved 76 on the respective appendages of the clutch cylinder 59. A Once the adjustment is finished, the fixing nut 89 must be tightened, against adjusting screw 86, to avoid a mismatch due to the vibrations caused during the movement of the vehicle.

Description of a material embodiment of the control module 9.

Figure 12 represents a top view of the Proposed material realization for the control module 9. The body control module 136 is defined as an extruded aluminum block, square section, where the housings have been mechanized for the different devices, the internal connections between said devices, communication ports with the outside, and threads for the different anchor bolts. Cylinder body 155, of automatic return cylinder 33, is connected by screws to body 136 and also serves as an anchoring element for solenoid valve 36. Anchor plate 165 is also is attached to the body 136 by screws and serves to make the anchoring of the control module 9, using the screws 166, in its corresponding location on the vehicle platform, in addition to serving as a support for overall 164, which prevents entry of harmful particles into the body 136 through of its opening for the exit to the outside of the joystick 138.

According to section E-E 'of the Figure 12, Figure 13 shows the construction details of the 27.35 microvalves and the devices in charge of carry out their operation, and the identification of their respective pneumatic connections.

According to section F-F 'of the Figure 12, Figure 14 shows the construction details of microvalves 30 and 34, of the devices in charge of carry out their operation of the return cylinder automatic 33, the identification of the corresponding ways of pneumatic connection and the symbolic representation of certain devices not found in the mentioned section.

After machining, on the faces of the body 136 the drills practiced to achieve the internal connection Drills that do not represent communication with the outside they are plugged by stainless steel balls. The exhaust ports of the different devices are communicated with the exhaust 167 of the control module, which can be seen in figure 12. Ports C1, C2, C3, C4, and C5, for connection with their homonyms in leveling module 7, they are grouped into the multiple connection base 50, where the corresponding one is coupled single hose connector politubo 10, which allows five independent ducts simultaneously and instantaneously.

About the material realization of the module command 9, it is important to note that the generic function of each of the individual devices and the interactions between them, to through internal connections, to achieve different functions, are exactly equivalent to those described with previously, in the explanation of the method, according to figures 2 and 3. For this reason, these explanations will not be repeated and, From here, the descriptions will aim at identification between the generic functions of each device of the method and material form in which this is achieved by Proposed material realization (parts, dispositions, etc ...).

Description of the material realization of the microvalves 27, 30, 34, and 35.

According to figures 13 and 14, it can be seen that microvalves 27, 30, 34, and 35 have identical building. These microvalves are configured as small pneumatic clapet distributors, three way and two positions, mechanically operated and with spring return. They find each other housed inside the body 136 and arranged in the part top of it, according to figure 12, equidistant from the axis length of the drive drum 137, as can be seen in figures 13 and 14.

According to Figure 13, when the microvalve 27 does not is activated, clapet 150 is held down on its lower seat due to spring 151 and air pressure existing in the upper feeding chamber (via C2), to which held incommunicado regarding the lower service chamber or exit (via C3). The inner hole and the lower holes of the sensor 144 represent the escape route of this distributor, with the one that communicates the lower service chamber (via C3) as there is no closing contact between clapet 150 and the upper end of sensor 144, which is held in that position thanks to the effort of the spring 148. When the microvalve 27 is operated by the corresponding manual device, sensor 144 it is displaced upwards, against the effort of the spring 148, to contact and also move to clapet 150, so the escape route is closed and the lower service chamber (via C3) communicates with the upper feed chamber (via C2) through the hole in the seat that the clapet has left open  150, generating a pneumatic signal that, through the connection C3, is responsible for conducting the corresponding pilot device in the leveling module 7. The same explanation serves to explain the operation of microvalves 30, 34, and 35, but changing the references to the respective lines of pneumatic connection

Description of the material realization of drive drum 137 and drive lever 138.

According to figures 13 and 14, it can be seen that the drive drum 137 has a cylindrical shape, with different steps according to the different diameters. It has a through transverse groove, where the lever is housed drive 138, and with a through transverse drill, perpendicular to said groove, to accommodate the shaft 139 anchor and turn for lever 138. Drum housing 137, inside body 136, is closed by the cover 141 which, in turn, it is immobilized thanks to retaining ring 143. The upper and lower ends of drum 137 are housed and supported, respectively and concentrically, in the background upper of the drum housing 137 and in the lid 141, of so that said drum 137 can only perform movements of rotation around its longitudinal axis, which obviously cannot move vertically. The body hole 136 which is traversed by lever 138, on its way out to the outside is shaped like a cross, to condition the possible shifts of lever 138 to those indicated in the Figures 12 and 13. This lever can move horizontally between positions I, II, and III, but can only move vertically between positions II, IIA and IIB.

According to figure 14, the upper face of the drum 137 has two protuberances that, acting as a cam, they can perform the vertical actuation of the sensors 144 of the microvalves 30 and 34 by the rotational movement of the drum 137. According to Figure 13, it can be seen that the lever of drive 138 has two upper protrusions that they can be located just below the sensors 144 of the microvalves 27 and 35, to be able to carry out the drive alternative of these by turning lever 138 around of axis 139.

According to figures 12, 13 and 14, when the lever 138 is in position I (vehicle circulation), none of the microvalves 27, 30, 34 or 35 are found powered. The horizontal rotation of lever 138, from position I  to position II (stop), implies the solidarity rotation of the drum 137 which, by means of one of its cams, performs the actuation of the micro valve 34 and activates a pneumatic signal through the line C5

According to Figure 13, the vertical rotation of the lever 138, from position II (stop) to positions IIA or IIB, does not cause any movement in the drum 137, so the micro valve 34 will remain actuated in these three positions of lever 138. The vertical rotation of lever 138, around the axis 139, to position IIA, will drive the micro valve 35, to activate a pneumatic pilot signal in the C4 connection, which will cause manual lifting of the platform vehicle. This elevation will stop at the moment the lever 138 is released and automatically returns to position II due to the spring 148 of the microvalve 35. The vertical rotation of lever 138, to position IIB, will drive of the microvalve 27, to activate a pneumatic pilot signal on connection C3, which will cause the manual descent of the vehicle platform, and will stop at the moment the lever 138 be released.

According to figures 12 and 14, the horizontal rotation of lever 138, from position II (Stop) to position III (automatic leveling in loading dock), involves the rotation solidarity of the drum 137 for, keeping the microvalve operated  34, now perform the additional actuation of the microvalve 30 by a second cam, in order to keep activated simultaneously the pneumatic piloting signals at the connections C1 and C5.

To make lever 138 fit perfectly located and slightly locked in all three different horizontal positions I, II and III, a specific positioning device. According to figure 14, it can be seen that the ball 160 is pushed by the spring 161 to be able to remain embedded, alternatively, in three accommodation carved on the cylindrical surface of the drum 137, defining three different locking positions for said drum 137, which coincide with the three possible horizontal positions I, II and III of the lever drive 138. Description of the material embodiment of the automatic return cylinder to position I 33.

According to Figure 14, it can be seen that the solenoid valve 36 can be activated, through the connection electric 37, to start the automatic return function of the lever 138 to position I (circulation), if not found  already in that position. When solenoid valve 36 is activated electrically, responds by performing the pneumatic feeding of the cylinder 33 from its connection with the pressurized air line C2, causing the displacement of piston 157, against resistance of the return spring 158, into the body 136. According to the Figure 13, it can be seen that drum 137 counts, in its part bottom left, with a drive plane. The stem of piston 157 pushes on said drive plane to make turn to drum 137 and, consequently, to lever 138 in the direction of return to position I. When the vehicle returns to be stopped, the electrical signal of movement reference will have ceased and piston 157 will have returned, due to the spring effect 158, to its resting position, so that the lever 138 of the module of command 9 can be used again normally.

It is susceptible of industrial application in the manufacture of pneumatic suspension control devices of industrial vehicles.

Claims (17)

1. Pneumatic suspension control method of industrial vehicles that, through the use of means mechanical-tires comprising a module of command and a leveling module, performs the functions of: A) Constant maintenance of the height of the platform during the movement of the vehicle, through a leveling valve actuated by a height sensor arm; B) Manual adjustment of platform height with the vehicle stationary, to level it with the spring load, by means of a manual up-down function; C) Limitation of the maximum height at which it can raise the platform to protect the suspension organs of the vehicle, by means of a height limiting valve; And it is also capable of performing the function from: E) Automatic return of the system to the function (A) of circulation height, by means of a piloted solenoid valve by an electrical signal generated when a certain optional control parameter; It combines the functions A), B), C), and E) Previous with a function: D) Constant level maintenance with the loading dock, during the entire loading or unloading process, of any platform height value that has been previously selected with the up-down function manual (B), regardless of the state of charge of the vehicle, characterized in that the constant maintenance function (D) level with the loading spring takes place by activating a pneumatic clutch (14) that establishes a temporary mechanical connection between the height sensing arm (8) and an intermediate arm (15 ) from the height previously selected with function B); so that variations with respect to said height cause the movement of the intermediate arm (15) which, by means of a compensating device (16), performs the alternative actuation of a feed sensor (17) or an exhaust sensor (18 ), which emit the respective pneumatic pilot signal that, through circuit selector valves (19 or 20), activates a pneumatic supply distributor (21) or a pneumatic exhaust distributor (22), which introduces or extracts air from the suspension lines (2, 3) of the vehicle, in order to restore the initially selected value for the self-leveling height of the platform at the loading dock, by mechanical means.
tires Method according to claim 1, characterized in that the compensating device (16) is an elastic means of transmission that deforms to absorb the additional displacement that the intermediate arm (15) can make after the corresponding feeding sensor (17 ) or exhaust (18) has been activated and reaches the top of its travel. Method according to claim 1, characterized in that the function of manually adjusting the height of the platform (B) is also carried out by means of the pneumatic feed (21) and exhaust distributors (22); since the pneumatic pilot signals sent, alternatively, from the control module (9), to order the elevation or manual descent of the platform, activate the pneumatic supply distributor (21) or the pneumatic exhaust distributor ( 22) after passing through the corresponding circuit selector valve (19 or 20), by the alternative route used by the supply (17) or exhaust (18) sensors during function D); to, in this way, introduce or extract air from the suspension lines (2, 3) and cause the vehicle platform to be raised or lowered to the desired height. 4. Leveling module for control of pneumatic suspension of industrial vehicles for, in cooperation with a control module, carry out the method of claim 1, comprising: a sensor arm (8) of the height variations of the vehicle platform which, through the axle resulting from the rigid and permanent union of semi-shafts (56.57), performs the drive of different internal devices of the leveling module; a leveling valve (12) which, actuated permanently by semi-axes (56.57), it maintains constant the movement height of the vehicle (function A); a height limiting valve (13) that, driven by semi-shafts (56.57), prevents excessive platform elevation (function C); a leveling mode selector valve (23) that, pneumatically piloted from a control module, determines the alternative connection of the leveling valve (12) or of the power distributors (21) and exhaust (22) with the pneumatic vehicle suspension lines; a feed check valve (eleven); a compressed air supply port coming from a boiler of the vehicle; communication ports with the lines of vehicle suspension; communication ports with a module command, from which the pneumatic pilot signals are received that determine the function to be performed by the module leveling; pressurized exhaust ports atmospheric; internal communications between the different individual devices and with communication ports Exterior; characterized in that, within the same block, it also includes: an intermediate shaft (15) which, by means of a compensating device (16), is activated by the semi-axles (56.57); a pneumatic clutch device (14) that, piloted from a manual control module, can be coupled temporarily with the semi-axles (56.57) through the intermediate shaft (15) and the compensating device (16); sensors, mechanical-tires, position (17, 18) actuated by the clutch cylinder (59) of the clutch device (14); a compensating device (16) for excess of displacement of the semi-axles (56.57) with respect to intermediate shaft (15); piloted pneumatic distributors, of supply (21) and exhaust (22), to introduce or extract air of the suspension lines through the selector valve of the leveling mode (23); circuit selector valves (19,20) for allow power distributors (21) and exhaust (22) are automatically piloted from the position sensors (17,18) or, alternatively, be piloted from a module manual control; so that: depending on the position selected in a manual control module, pneumatic piloting will be established on different leveling module devices that will determine different modes of operation of pneumatic distributors of supply (21) and exhaust (22); pneumatic feed distributors (21) or exhaust (22) can alternatively be piloted from a manual control module, through the corresponding valve circuit selector (19 or 20), to introduce or extract air from the suspension lines through the mode selector valve leveling (23), and thus be able to execute the adjustment function platform height manual (function B); after activation of the clutch device (14), pneumatic feed distributors (21) or Exhaust (22) can be respectively piloted by the sensors supply (17) or exhaust (18), through the corresponding circuit selector valve (19 or 20), for introduce or extract air from the suspension lines and, so automatic, keep constant level with the loading dock, during the entire loading or unloading process, any value of platform height that has been previously selected with function B), regardless of the state of charge of the vehicle (function D). 5. Leveling module according to claim 4, characterized in that the main rod (40) of the sensor arm (8) is actuated through its mechanical connection with the reference wheel axle (6) when variations in height occur of the platform, which causes the rotation movement of the rigid shaft formed by the two semi-axles (56,57) to directly drive the leveling valve (12) and the height limiting valve (13), and is also capable of activating to the supply (17) or exhaust (18) sensors, by means of the temporary mechanical connection between the clutch device (14) and the semi-axles (56,57), through the intermediate shaft (15) and the compensating device ( 16), provided that said clutch device (14) is activated. 6. Leveling module according to claims 4 and 5, characterized in that the activation of the pneumatic clutch device (14) establishes its temporary mechanical connection with the semi-axles (56,57), through the intermediate axis (15) and the compensating device (16), from the previously selected height by means of the manual low-rise function (B) as self-leveling height; clutch device (14) which, when variations occur with respect to said height and by means of the drive appendages of its clutch cylinder (59), performs the alternative actuation of the feed sensor (17) or the exhaust sensor (18), the which emit the corresponding pneumatic pilot signal which, through the respective circuit selector valve (19 or 20), activates the pneumatic supply distributor (21) or the pneumatic exhaust distributor (22), which introduces or extracts air from the suspension lines, through the leveling mode selector valve (23), in order to automatically restore the value initially set for the platform height to be leveled at the loading dock, thus performing the maintenance function constant level with the loading dock (D). 7. Leveling module according to claims 4 and 6, characterized in that the compensating device for excess displacement (16) is composed of two semi-clamps (71,73) and a torsion spring (72) which, previously prestressed and with the hinges of its two ends anchored respectively to each of the two semi-clamps (71.73), it generates a torque that pushes said semi-clamps (71.73) according to opposite directions of rotation, for, in the intermediate space to them, keep pressed and aligned two appendices of the semi-axis II (57) and the clutch disc support (68); Therefore, during function D), the intermediate shaft (15) and the clutch device (14) will rotate in solidarity with the semi-axles (56.57) until, after actuating the position sensors (17 or 18), the clutch cylinder drive appendages (59) reach their turning stops within their housing, the clutch device (14) and the intermediate shaft (15) being immobilized, while the semi-axles ( 56.57) they can continue their rotational movement after the tightening spring pre-tension effort (72) has been exceeded. 8. Leveling module according to any one of claims 4 to 7, characterized in that the supply (17) and exhaust (18) sensors have a vertical adjustment inside their housing, by threading or unscrewing the adjusting screw (86 ) with respect to the sensor closure (88), to move the sensor body (79) and correctly adjust the contact distance between its sensor rod (76) and the actuation plane in the corresponding appendix of the clutch cylinder (59). 9. Leveling module according to any one of claims 4 to 7, characterized in that the final section of the pneumatic line that communicates directly with the clutch device (14) from within the leveling module, is constituted by a tube (117 ) flexible and by the corresponding two connectors (116) connecting their ends; so that the flexibility of said tube (117) allows pneumatic communication with the clutch device (14) despite the movements it can perform during the function
D). 10. Leveling module according to claim 4, characterized in that it comprises a main body (51), a distributor body (44), and a clutch housing (52); that house the constituent parts of the different individual devices and the different communication channels between said devices, in addition to the communication ports with the outside. 11. Leveling module according to claims 4 and 10, characterized in that the input shaft formed by the two semi-axes (56, 57) is housed and supported, in its length external to the main body (51), by the housing clutch (52); mounted on the semi-shafts (56, 57) and housed by the clutch housing (52) are the compensating device (16), the intermediate shaft (15) and the clutch device (14), so that the appendages of the Clutch cylinder (59), of the clutch device (14), have specific housings inside the main body (51) to be able to drive the position sensors (17, 18) that are located in that same location within of the main body (51), specific housings that also perform the function of limiting the rotation movement of the clutch device (14). 12. Control module for pneumatic suspension control of industrial vehicles for, in cooperation with the leveling module of claim 4, to carry out the method according to claim 1, characterized in that it comprises: pneumatic microvalves (27, 30, 34, 35), mechanically operated, to perform the piloting of different devices of the corresponding leveling module and select thus the different functions that this one can execute; a drive lever (138) and a drum drive (137), articulated with each other by an axis (139), to effect the selective actuation of the four micro valves (27, 30, 34, 35) depending on the five different positions (I, II, IIA, IIB, and III) that said lever can occupy (138) through manual operation thereof; an automatic return cylinder (33) which, when be fed pneumatically, it acts mechanically on the drum (137) to perform the return rotation of the lever (138) to your initial position (I); a solenoid valve (36) which, upon activation by means of an electrical signal through the connector (37), it performs the automatic return cylinder feed (33); non-return valves (29), interposed in the conduits that feed the microvalves 30 and 34; positioning devices composed of a ball (160) and a spring (161), to determine three different locking positions in the drum rotation (137), which conditions three different locking positions for the horizontal rotation drive of the operating lever (138);

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some communication ports with the corresponding leveling module, to which the pneumatic piloting signals that determine the function to be performed by said leveling module, and from which a line is received for pneumatic supply of the control module (9); a pressurized exhaust port (167) atmospheric 13. Control module according to claim 12, characterized in that the operating lever (138) is forced to move into a cross-shaped groove, whose four ends and whose center determine the five different positions that said lever can occupy ( 138), which can move horizontally between positions I, II, and III, and can only move vertically between positions II, IIA and IIB, with position II as central position; five different positions that give rise to different combinations in the mechanical actuation of the four microvalves (27, 30, 34, 35), performed by the lever (138) and the drum (137), to effect the consequent pneumatic piloting of different devices in the corresponding leveling module and thus be able to select the function that said leveling module must perform. 14. Control module according to claims 12 and 13, characterized in that the drive drum (137) can only make rotational movements, about itself, around its longitudinal axis, and incorporates a through transverse groove in which it is housed the inner end of the actuating lever (138) and a through transverse bore, perpendicular to said groove, where the axis (139) for anchoring and turning the lever (138) with respect to the drum (137) is housed, so that the horizontal displacements of the lever (138) force it to rotate in solidarity with the drum (137) and the vertical displacements of said lever (138) allow it to rotate with respect to the drum (137) without causing any movement in the latter; The upper side of the drum (137) has two protuberances that, by way of cams, can perform the vertical actuation of up to two of the four microvalves (27, 30, 34, 35), which on 61 are located, by means of rotation of the drum (137) by the horizontal displacement of the lever (138); the actuating lever (138) also has two protuberances at both ends of its interior area to the drum (137), which can protrude with respect to the upper face of said drum (137) to perform the vertical actuation of the two remaining microvalves, alternatively, by rotating the lever (138) with respect to the drum (137), in one direction or another, when said lever (138) moves vertically. 15. Control module according to any of claims 12 to 14, characterized in that the four microvalves (27, 30, 34, 35) are located on the upper face of the drive drum (137), with their longitudinal axes parallel to the axis longitudinal of said drum (137), around which they are distributed; so that in position I of the joystick (138) none of the micro valves are operated; by moving the lever (138) horizontally to position II, one of the drum cams (137) activates the microvalve 34 (stop or stop), which will also remain actuated in positions IIA, IIB and III; by moving the lever (138) upwards, from position II to position IIA, said lever (138) activates the microvalve 35 (lift platform) and, due to the spring (148) of the microvalve 35, the lever (138) will automatically return to position II, after being released from the manual actuation effort, and the activation of the microvalve 35 will cease; by moving the lever (138) down, from position II to position BB, said lever performs the activation of the microvalve 27 (lowering the platform), also automatically returning to position II after being released and ceasing to operate the microvalve 27; when the lever is moved horizontally, from position II to position III, the other drum cam (137) drives the microvalve 30 (self-leveling in loading dock). 16. Control module according to any of claims 12 to 15, characterized in that the solenoid valve (36), when activated from the electrical connection (37), establishes the pneumatic supply of the return cylinder (33) for, by means of the stem (157), make an axial thrust force on the corresponding drive plane of the drive drum (137) and generate the necessary torque to rotate said drum (137) in the direction of returning the drive lever (138) to its position I, in the case of not already being in said position, (function E). 17. Control module according to any one of claims 12 to 15, characterized in that the ball (160) is pressed by the spring (161) to alternatively fit into one of the three housing grooves carved on the surface cylindrical of the drive drum (137), defining three different interlocking positions in the angular travel of said drum (137) and constituting a locking or interlocking device for the three selective positions (I, II, and III) of the lever drive (138) in the horizontal path of its manual drive.