WO2010028463A1

WO2010028463A1 - Process and device for damping of impacts

Info

Publication number: WO2010028463A1
Application number: PCT/BR2008/000272
Authority: WO
Inventors: Ronaldo Santos Pereira
Original assignee: Ronaldo Santos Pereira
Priority date: 2008-09-09
Filing date: 2008-09-09
Publication date: 2010-03-18

Abstract

Process and device for damping of impacts, device that allows, of controlled way by computer, to reduce impacts received in its extremity and that also allows the execution of commands received from other application systems. The device is formed by a mobile part (1 ) that is moved in direction to the fixed base (5), when this receives a force originated from an external impact. The damping is made through magnetic field generated by electromagnet(s) (6,7), which force is opposed to the movement of the mobile part (1 ). The intensity and kind of the said field are controlled by system of dedicated control. Such system is capable still of receiving and prosecuting commands derived of external systems.

Description

"PROCESS AND DEVICE FOR DAMPING OF IMPACTS"

The present invention refers to a process and device that allows, in way controlled through computer, soften impacts received in its extremity and that also allows the execution of commands received from other systems applications.

Currently, several devices are used in the control of forces and impacts in the industries, as part of the industrial processes. Such devices are also many used in the own constitution of several products.

The springs and pneumatic devices are usually the most used for this end, besides the use of materials of larger resistance and/or flexibility, when it is looking for minimizing the effects of a possible force generated by an impact.

Such devices however have some characteristics in common:

• They don't allow the control of their damping action;

• They are reactive, in other words, they just get to react to an event when this is already present, what reduces their effectiveness and efficiency;

• They are built to assist to forces whose intensity is limited to a narrow variation field, turning them innocuous when submitted to intensity forces out of this field.

The present invention has as objective especially to avoid the inconveniences above mentioned, presenting for that a damping device that, controlled through specialized software and hardware, is capable to adapt itself to the received force, whose intensity can be contained in a wide variation field. Moreover, the present invention has the objective of allowing its adjustment in advance to the certain force, whose occurrence was foreseen through commands or special sensors connected to the control system.

To reach the objectives above delineated, the present invention establishes a damping process that uses a magnetic field, whose controlled variation of intensity and polarization will allow to control and to be opposed to the force resultant of a certain impact that is wished to reduce.

The present invention establishes the control of this magnetic field through the variation of the electric power supplied to electromagnets especially placed in order to obtain the controlled damping effect of the received impacts.

Therefore, the present invention establishes, in general lines, a device that owns a mobile part and a fixed part, regarding the surface that is wished protect of the impacts. The mobile part, which will receive the impact to be damped, will be connected to an electromagnet that, then, will be under the effect of a magnetic field generated by a second electromagnet, which we will be affixed to the fixed base.

The operation of the device will occur by the movement of the mobile piece that, when receiving a certain force on its extremity, will dislocate in direction to the fixed part of the device. However, the magnetic field generated by the electromagnet present inside the fixed part will be able to be used to repel or to attract the electromagnet connected in the mobile part, which will make possible the control of the damping process, through the generation of a contrary force or a force in the same direction of the movement of the mobile part. The activation of the repulsion or attraction process can be controlled through the inversion of the polarity of the used electromagnets, what is done alternating the polarity of the electric power supplied to these electromagnets.

So that the control of the damping process be possible, it will be necessary still the existence of a control system able to supply information as position, speed and acceleration of the first electromagnet regarding the second electromagnet. Based on this information, the control software can define which the necessary changes are in the continuous electric current supplied to both electromagnets, with the objective of making the damping process with maximum efficiency and effectiveness.

Thus, the present invention also refers to the control of impacts process, to be executed by a control system formed by hardware and software especially developed for this end. The hardware will be an electronic circuit having a sensor device capable of detecting the movement of the piston generating signals, which will be converted from analogical format to digital format via ADC and soon after sent to a programmable microcontroller. This, then, prosecutes the received signals, calculating the due damping force and consequent alteration of current/tension to be applied to the electromagnets through appropriated formulas. These alterations are transformed in digital commands that are converted to analogical signals through a DAC, or even for a digital potentiometer that was behaved as DAC.

This electronic circuit will also have a communication resource with external computerized system, through signals in the formats: serial, parallel or another, according to application.

The present invention also refers to the software that composes the control system, which will be presented and then executed continually by the programmable microcontroller circuit above referred. This software, which basic flowchart will be detailed further in the present document, will be responsible for the treatment of events and commands received by the control system.

The present invention also establishes that the controlled damping device can use only the principle of the magnetic field as a damping way or still it can use it of an associate way with other traditional means of damping, like springs or pneumatic devices.

Considering the technological evolution represented by discovery of the "superconductors" materials, the present invention can have its efficiency improved through the utilization of the said "meissner" effect, described by the physicists W. Meissner and R. Ochsenfeld in 1933, and that is observed when a superconductor material is submitted to a magnetic field. As the superconductor material is diamagnetic, it prevents the entrance of the magnetic field in its structure, being repelled by the same.

Therefore, the present invention also refers to a variation of the controlled damping device, where one of the electromagnets is substituted by a pastille formed by superconductor material.

The superconductor materials current known need to be frozen in very low temperatures so that its superconductor capacity be usable. Thus, the diamagnetic pastille should be built of superconductor material immersed in nitrogen in liquid state and packed in a capsule of non-metallic material, like rigid plastic or PVC. The interior side of the plastic capsule should be covered by a rigid polyurethane coat, which will serve as thermal insulating and will keep the temperature inside the capsule. The thickness of rigid polyurethane coat should be defined according to volume of liquid nitrogen stored inside the capsule.

Other characteristic of the invention are:

• The dimensions and the composition of the elements used in the device will vary according to the application of the same.

• The kind of the material that should be used in the construction of the mobile part and fixed base could be metals as steel, stainless steel, brass, etc, besides other rigid materials as plastic, etc, according to aesthetics need, resistance, weight and other important characteristics for the application. • To decrease the interference in the magnetic field to be generated inside the fixed base of the device when the same is constituted of conductive material, its internal part can have a coat of insulating material, whose thickness will depend on the power of the said field.

• The length of the mobile part should be enough to allow its movement regarding the fixed part. Moreover, it should allow the complete approach between electromagnet or diamagnetic pastille and the electromagnet of the fixed base. • The maximum distance of action of the magnetic field generated by the(s) electromagnet(s), when this(these) is(are) with its(their) minimum capacity of projected energy, they will serve as parameter for the definition of the maximum distances allowed between electromagnets (or diamagnetic pastille) .

• It can be used electromagnet of industrial production whose format and power can vary according to the application.

• The electromagnetic power of the employed electromagnet(s) will define the performance field of the damping device.

• The energy to be supplied to the electromagnet(s) should be arising of one or more batteries or generator sources external to the device, whose voltage and capacity will depend on the application and of the characteristics of components employed in the montage of the device.

The description that is followed and the associated figures, all presented in a non-limited way, will make the invention very comprehensible.

Figure 1 presents an example of complete device that uses the impacts control through magnetic force associate to a spring, according to invention.

Figure 2 presents, in cut, the same device of figure 1 , detailing all the internal parts that compose it, according to invention.

Figure 3 presents an example of the "meissner" effect. The magnet 1 generates a magnetic field 2. The force lines of this field can't penetrate inside the diamagnetic object (superconductor) 3. Therefore, the magnet 1 "floats" over the superconductor 3, since the repulsion force of the magnetic field compensates the gravity force on the same.

Figure 4 shows in general lines the constitution of the diamagnetic pastille used in the composition of the device, according to invention.

Figure 5 exemplifies the montage of a diamagnetic pastille, according to invention.

Figure 6 is a schematized view, and in blocks, of the electronic part of the control system to be used together the device, according to invention. Figure 7 is a basic flowchart of the software to be executed by microcontroller that composes the said control system, according to invention.

Figure 8 is a schematized view of a sensor device example that can be employed as part of the control system, according to invention. In the figures 1 and 2, there is an example of device for damping of impacts that uses, of a combined way, magnetic field and a spring. The construction process of the device can vary according to the material employed in its constitution.

It can be observed its basic constitution of a mobile part, formed by items marked as 1, 2, 3 and 6 and of a fixed part, formed by items marked as 4, 5, 7 and 8. In the said example, it is considered that all items are made of steel.

The surface (1) represents the area that will be subjected to the impact to be damped. Therefore, its constitution should be sufficiently resistant to support the impacts inside the band waited by project of the application. Its diameter should be greater than the diameter of the orifice of the fixed base (4), in order to prevent the dismount of the device. In the said example, the spring (3) is also used as a damping way. Its constitution and thickness should be defined according to the need of application.

The piston (2) is the unique part of the mobile piece that penetrates inside the fixed part (5), through the orifice (4). Such orifice has a reinforced brim in order to reduce the lateral movement of the mobile part. In the extremity of the piston (2), in the internal part of the fixed part (5), the electromagnet (6) is connected.

In the base of the fixed part (5) it is the electromagnet (7) which will exercise influence on the electromagnet (6).

To allow the montage of the device, the fixed base (5) is opened in its inferior part, and the electromagnet (7) could work as closing cover of the same, and it will be fixed through lateral screws.

To reduce the emission of electromagnetic radiation generated by the device, the base (5) can have an appropriated shield (8) as, for instance, a "mu-metal" coat, depending on the application. The montage process is initiated by soldering of the piston (2) to the electromagnet (6). The type of used soldering will vary according to material employed in the composition of both. The montage of the fixed part also is initiated, with the drilling of the base (5) in its superior part and consequent soldering of the brim (4) in the orifice, through where the piston should move.

After for soldering, the piston is put into the orifice (4), through the opening in the underside of the fixed part (5). Then the spring (3) is fit in the external part of the piston and, in its extremity, the surface (1) is soldered.

The montage of the device can be then concluded through the placement of the electromagnet (7). It should pay attention to the placement of the energy supply cables for the electromagnets through special drillings made in the fixed base (5), before the closing of the device. The device object of this invention should be fixed on a resistant surface, according to the needs of application.

In the figure 4, it is shown, in cut, an example of a pastille made of superconductor material. According to invention, the external involucre (1) should be made of non-metallic material, like rigid plastic. In the walls of the involucre (1) should be applied a rigid polyurethane coat (2) which will have the function of thermal insulating and will also act as barrier against the leak of the content of the pastille.

In the figure 5, it can be observed with more details an example of pastille with superconductor material, according to invention, made of PVC. In the cut A, it can be observed that the pastille is made of two parts: a superior part (1), which works as a cover to the inferior part (2). In the cuts B and C, it is observed, in cut and in angle of frontal way, the montage details: the cover (1) has diameter lightly larger, in order to allow the threading of the same in the base (2). In the said example, the cover (1) is 2 millimeters greater than the base (2).

To prevent leaks of the liquid nitrogen, which will be stored in the internal hollow part (6) it will be necessary that, in the action of the threading, is used a stanching ribbon. Still to allow the threading, the internal part (5) of the cover (1) and the external part of the base (2) should have grooves. In the interior side of both parts (1) and (2) should be applied a rigid polyurethane coat (3). In the cover (1), however, this polyurethane coat should allow the perfect fit of the brim (4) of the base (2), what will guarantee larger stanching to the pastille.

As previously said, the internal part (5) will shelter the superconductor material immersed in nitrogen in liquid state. For larger warranty against leaks, both should be packed in a thermo-stamp plastic sack, like PP.

Thus, during the montage process, a sack of PP kind is filled out with superconductor material as, for instance, the ceramic Hg_OsTl₀₂Ba₂Ca₂Cu₃O_{8 33} and nitrogen in liquid state (with temperature below 77K) and, soon after, is stamped through thermal industrial stamping. After that, the sack is packed inside the base (2) which is covered, through threading, by the cover (1). The superconductor material cited as example is a ceramic that has high Tc (critical temperature), in other words, it has superconductor capacity at temperatures up to 138K.

The pastille, thus mounted, can then replace one of the electromagnets that compose the damping device, as the invention.

The present invention also refers to the control process of the damping, which will be accomplished by a system that should allow the control of the movement and positioning of the mobile part related to the fixed part of the device.

This control system will be formed basically by hardware and software. In the figure 6, it can be seen a basic outline of the system hardware part: the movements of the piston (1) are monitored by sensor device (2). Such device can be constituted of several sensors resources currently used, such as: frequency radio (RF), optic sensor, tension/current scales, etc, according to the needs of application.

As an example, in the Figure 8 it is introduced a schematized process and simple sensor set capable of monitor the movement of the piston:

A metallic jagged wheel (5) has its axis fastened to the external surface of the fixed part of the device by a support (6). Their teeth are in touch with a scale in relief (4), especially placed in the lateral of the piston (3), what it makes rotates around its axis in case of movement of the same. In each level of the referred scale (4), there is a termination of an isolated circuit formed by an only source (1) to all circuits and a specific Zener diode (2). This diode will be responsible to for keeping the tension in this circuit in a pre-established level, different from the other circuits. The jagged wheel (5) then is connected to the converter device (7), through its base (6). When the referred teeth of the jagged wheel connect the certain termination, the circuit is closed, generating a signal whose tension/current is different from all the rest of the circuits. This way, it can mount a relationship table between one determined tension/current and a determined position of the piston, regarding the fixed part of the damping device. Back to the explanation base on figure 6, the signals generated by the sensor device must then be directed to a device (3) of Conversion of Analogical Signals to Digital Signals (ADC). This circuit will transform the signal in a format that can be comprehended by programmable microcontroller (4). Microcontroller (4) is the responsible for the management of the whole damping process. That will be made through execution of specialist embarked software. When receiving the interruption of the ADC (3), it will execute own routine to calculate which action should be taken, regarding the increase/decrease of the power of the electromagnets 1 and 2. Before, however, their commands are passed to the device (5) of Conversion of Digital Signals to Analogical Signals (DAC), so that they can be applied to the electromagnets (7 and 9), changing, therefore, the magnetic field (8) between the same ones.

The present invention establishes that microcontroller (4) can also receive commands coming from external sources. This communication can be made by communication device (6) of the kind: serial, parallel or another, according to application. In the figure 7, it is shown the basic flowchart operation of the software to be put into microcontroller, according to present invention.

This software has a central module and two interruption treatment subroutines. The central module is in continuous loop, just counting time and verifying the occurrence of interruptions originated from the arrival of some external command (1) or of some event of the sensor system (2).

In case of receipt of external command, the subroutine "A" is activated, where the command is properly read (3) and interpreted (4).

As example of possible external commands that could be implemented, it can be cited the command of gathering the piston, which would be done through the inversion of the polarity of one of the electromagnets, making a field of attraction appears between the same ones.

Other example of external command would be the maximum exposing of the piston, through the increase of the magnetic field of repulsion between electromagnets.

Thus, each kind of command should have its corresponding processing (5), and its posterior sending to the module DAC (6).

The subroutine "B", then, will be activated in the receipt of the events of the movement sensor of the piston. The events are then read (7) and the next information is extracted (8): current position, speed and acceleration of the piston.

In general, the information supplied by sensor to microcontroller through ACD will make reference to a determined tension/current variation. This variation can be confronted with a pre-defined table that will allow the discovering of the current position of the piston related to the fixed part. Moreover, keeping in mind times of each event saved in memory by microcontroller, it can calculate the speed of the piston, by the formula: V = (X - Xo) / (t - to). Acceleration then can be deduced from formula: A = (V - Vo) / (t - to). Calculations will be then made (9) of the necessary force for the damping process, as well as of the necessary tension/current. So that the damping occurs, it will be necessary the application of a contrary force to the movement of the piston, in other words, a negative acceleration. However, to have the best performance of the device, with a minimum of energy expense and a minimum of reactive impact, the total paralyzation of the piston should only occur when the piston reach its maximum position. This way, it should be used the following formula in the calculation of the force to be applied on the piston:

F = - Vxo² * M / 2 * (X - Xo)

Where:

Vxo = current speed of the piston;

M = mass of the mobile part of the device;

X = maximum position that the piston can reach;

Xo = current position of the piston.

The current to be applied to the electromagnets will have then to be deduced through correlation table between supplied energetic power and force of magnetic field, supplied by the manufacturer of the electromagnet.

In the fault of that, it can be used the relation:

H = (N / L) * I Where:

H = intensity of the generated magnetic field; N = number of spires of the electromagnet; I = Intensity of the supplied electric current;

L = distance between the polar regions of the bobbin;

It must be still considered the fact that the magnetic force in a given point is inversely proportional to the square of the distance from its source. Thus, the found result should be multiplied by this value to guarantee the operation of the damping process.

After these calculations, it will be sent (10), through DAC device, the necessary command to the electromagnets to make the wished damping.

Claims

1. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", an impact damping device, wherein the control of the damping process is made of a computerized way, through system of specific control, which allows the execution of commands received from other application systems.

2. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", device according to claim 1, wherein it is formed by a mobile part that is moved regarding a fixed part when receive a resultant force of impact.

3. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", device according to claim 1, wherein the damping is made through the set of magnetic field associated or not to traditional means of damping.

4. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", device according to claim 3, wherein it is employed electromagnet(s) like generator(s) of the magnetic field.

5. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", device according to claims 1 to 4, wherein an electromagnet is connected in the extremity of the mobile part and a second electromagnet is fastened in the base of the fixed part, and both generate magnetic influence to each other.

6. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", device according to claim 5, wherein it can be employed a pastille of superconductor material, in substitution to one of the electromagnets, according to application.

7. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", device according to claim 6, wherein, in this case, it is employed the "meissner" effect in its operation.

8. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", device according to claim 6, wherein, in case of the superconductor material needs a special refrigeration, the pastille of superconductor material can be made for superconductor material immersed in nitrogen in liquid state wrapped in a capsule of non-metallic material, whose interior side is covered by a rigid polyurethane coat.

9. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", an impacts damping process, according to claims 2 to 7, wherein:

• The mobile part dislocates in direction to the fixed part, due to the impact received in its extremity; • The movement of the mobile part is braked through contrary force exercised by the magnetic field of repulsion existing between electromagnets, or through the "meissner" effect observed between electromagnet and pastille of superconductor material; 10. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", the device according to claims 1 to 5, wherein it has a control system of the damping of impacts process, composing by: movement sensor device of the piston, signals conversion device of analogical format to digital format (ADC), programmable microcontroller, conversion device of digital signal to analogical signal (DAC), external communication device and embarked software.

11. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", the control process of the impacts damping accomplished by the control system, according to claims 9 and 10, wherein:

• The sensor device detects the occurrence of the piston movement and generates analogical signals that are transmitted to ADC; • ADC converts these signals to the digital format and sends them to microcontroller;

• The microcontroller, through specialist software, treats the received event and calculates: position, speed and acceleration of the piston;

• The microcontroller calculates the necessary force to reduce the movement of the piston and the necessary alteration of the electric current/tension supplied to the electromagnets;

• The microcontroller transmits the command in digital format to the device DAC;

• The DAC device converts the digital command to the analogical format and executes the requested alteration.

12. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", the execution process of external commands received by the control system, as claims 1 and 10, wherein:

• The communication device receives the command derived of external application system and generates an interruption in microcontroller;

• The microcontroller, through specialist software, interprets the received command and calculates the necessary alteration of the electric current/tension/polarity supplied to the electromagnets;

• The microcontroller transmits the command in digital format to the DAC device; • The DAC device converts the digital command for the analogical format and executes the asked alteration.

13. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", the movement sensor device of the piston, according to claims 10 and 11, wherein it is composing by: series of circuits isolated with single source and tension regulator {zener diode) differentiated for each circuit, which feed a scale in relief placed over the lateral surface of the piston that then is connected to a jagged wheel capable of establish connection with the remaining of the control system.

14. "PROCESS AND DEVICE FOR DAMPING OF IMPACTS", the monitoring process of the movement of the piston through sensor device, as claim 13, wherein:

• The movement of the piston makes rotate the jagged wheel that makes the connection to other level of the scale in relief existed in the surface of the piston;

• This makes the new circuit to be closed, generating a signal with different tension level; • The tension variations are detected by ADC device, allowing the monitoring of the movement of the piston.