Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B08—CLEANING
  • B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
  • B08B15/00—Preventing escape of dirt or fumes from the area where they are produced; Collecting or removing dirt or fumes from that area
  • B08B15/02—Preventing escape of dirt or fumes from the area where they are produced; Collecting or removing dirt or fumes from that area using chambers or hoods covering the area
  • B08B15/023—Fume cabinets or cupboards, e.g. for laboratories
• • E—FIXED CONSTRUCTIONS
  • E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
  • E05D—HINGES OR SUSPENSION DEVICES FOR DOORS, WINDOWS OR WINGS
  • E05D13/00—Accessories for sliding or lifting wings, e.g. pulleys, safety catches
  • E05D13/10—Counterbalance devices
  • E05D13/14—Counterbalance devices with weights
• • E—FIXED CONSTRUCTIONS
  • E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
  • E05F—DEVICES FOR MOVING WINGS INTO OPEN OR CLOSED POSITION; CHECKS FOR WINGS; WING FITTINGS NOT OTHERWISE PROVIDED FOR, CONCERNED WITH THE FUNCTIONING OF THE WING
  • E05F5/00—Braking devices, e.g. checks; Stops; Buffers
• • E—FIXED CONSTRUCTIONS
  • E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
  • E05Y—INDEXING SCHEME RELATING TO HINGES OR OTHER SUSPENSION DEVICES FOR DOORS, WINDOWS OR WINGS AND DEVICES FOR MOVING WINGS INTO OPEN OR CLOSED POSITION, CHECKS FOR WINGS AND WING FITTINGS NOT OTHERWISE PROVIDED FOR, CONCERNED WITH THE FUNCTIONING OF THE WING
  • E05Y2201/00—Constructional elements; Accessories therefore
  • E05Y2201/20—Brakes; Disengaging means, e.g. clutches; Holders, e.g. locks; Stops; Accessories therefore
  • E05Y2201/21—Brakes
• • E—FIXED CONSTRUCTIONS
  • E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
  • E05Y—INDEXING SCHEME RELATING TO HINGES OR OTHER SUSPENSION DEVICES FOR DOORS, WINDOWS OR WINGS AND DEVICES FOR MOVING WINGS INTO OPEN OR CLOSED POSITION, CHECKS FOR WINGS AND WING FITTINGS NOT OTHERWISE PROVIDED FOR, CONCERNED WITH THE FUNCTIONING OF THE WING
  • E05Y2201/00—Constructional elements; Accessories therefore
  • E05Y2201/40—Motors; Magnets; Springs; Weights; Accessories therefore
  • E05Y2201/46—Magnets
  • E05Y2201/462—Electromagnets
• • E—FIXED CONSTRUCTIONS
  • E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
  • E05Y—INDEXING SCHEME RELATING TO HINGES OR OTHER SUSPENSION DEVICES FOR DOORS, WINDOWS OR WINGS AND DEVICES FOR MOVING WINGS INTO OPEN OR CLOSED POSITION, CHECKS FOR WINGS AND WING FITTINGS NOT OTHERWISE PROVIDED FOR, CONCERNED WITH THE FUNCTIONING OF THE WING
  • E05Y2201/00—Constructional elements; Accessories therefore
  • E05Y2201/60—Suspension or transmission members; Accessories therefore
  • E05Y2201/622—Suspension or transmission members elements
  • E05Y2201/644—Flexible elongated pulling elements; Members cooperating with flexible elongated pulling elements
  • E05Y2201/652—Belts
• • E05Y2999/00—

Definitions

• TITLE Braking device for laboratory fume hood mobile window
• Such a laboratory hood shown in Figure 1, is generally in the form of a cabinet of substantially parallelepipedal shape, comprising in its lower part a handling bench 1, and in its upper part an enclosure 3 whose front face can be closed by a window 5 sliding vertically.
• a system of cables 7, return pulleys 9a, 9b and counterweights 11, the weight of which is slightly lower than that of the window 5, makes it possible both to facilitate the opening of the window by the laboratory worker, and to avoid the sudden closing of this window.
• the hood is designed to operate with the window closed or partially closed (in particular when one wishes to increase the gas extraction rate), in order to protect the health of the laboratory workers.
• the present invention aims in particular to provide a simple and safe system for maintaining the window in a fully open position or intermediary, allowing time for the laboratory technician to intervene before the window automatically falls under the effect of its own weight.
• the present invention relates to a braking device for a mobile window of a laboratory fume hood, comprising a magnetic compensator and means of connection to a system counterweighting said window, in which said magnetic compensator is of the type with electromagnet, the braking being performed when the electromagnet is not electrically powered, and being released when the electromagnet is electrically powered.
• the window is released, so that it can automatically return to its closed position under the effect of its weight, or else be easily opened by the laboratory worker.
• the electromagnet is therefore only supplied occasionally, which is very economical from an energy point of view.
• said connecting means comprise a belt drive pulley cooperating with said counterweight system
• said magnetic compensator comprises: at least one first brake disc mounted fixed in rotation and free in translation with respect to said electro -magnet, at least one second brake disc mounted fixed in rotation and free in translation with respect to said pulley, at least one brake pad interposed between said first and second brake discs, mounted free in rotation and in translation with respect to said electromagnet, and a spring interposed between said electromagnet and said first brake disc, elastically biasing said first brake disc against said brake pad, and said brake pad against said second brake disc:
• This device comprises washers for adjusting the compression of said spring: these washers make it possible to calibrate the compression force of the spring, and thus to guarantee the braking of the window;
• this device comprises means for supporting said magnetic compensator and said pulley shaped to allow mounting of this magnetic compensator and this pulley on a wall of said hood either with their axis perpendicular to this wall, or with their axis parallel to this wall: this conformation of the support means makes the device according to the invention versatile, that is to say adaptable to any form of hood furniture and to any type of counterweight system (one or more counterweights, one or more cables, different cable routing geometries, etc.);
• the present invention also relates to a fume hood comprising a movable window and a counterweight system to this window, comprising a braking device according to the above, connected to this counterweight system.
• a fume hood equipped with this device has the required characteristics for controlling the sliding movement of the window under optimum safety and reliability conditions.
• this hood further comprises an intrusion detection barrier inside the volume of the hood: such a barrier makes it possible to stop the downward movement of the window when a laboratory worker interferes with the interior volume of the hood. hood enclosure;
• This hood further comprises means for determining the position of said window: these position determining means make it possible in particular to adjust the position of the window according to the desired air extraction rate.
• the present invention also relates to an electronic supervision device for a laboratory fume hood in accordance with the foregoing, comprising electrical connection means in particular to said magnetic compensator, to said detection barrier and to said discrimination means, and means management of the signals sent by these bodies, and development of control signals of these bodies.
• Such a supervision device ensures coordination between all the electrical and electronic components of the hood; it can also liaise with other similar supervision devices placed on other hoods, and/or communicate with a supervision center which controls a battery of hoods.
• FIG. 1 a conventional hood shown schematically in side view, as described in the preamble to the present description
• FIG. 2 a hood according to the present invention shown schematically in front view, with indication of the electrical and mechanical connections between the various elements involved in controlling the lowering movement of the window;
• FIG. 3 an exploded perspective view of the braking device as mentioned;
• FIG. 4 an exploded perspective view of the magnetic compensator of this device
• FIG. 5 a side perspective view of this magnetic compensator in the released configuration
• FIG. 6 a side perspective view of this magnetic compensator in the braked configuration
• FIG. 7 a perspective view of the braking device according to the invention when it is mounted inside a laboratory fume hood wall, according to a first mounting configuration
• FIG. 8 a perspective view of the braking device according to the invention when it is mounted inside a laboratory fume hood wall, according to a second mounting configuration.
• hood H comprising in its lower part a bench 1, and in its upper part an enclosure 3 which can be closed by a window 5 able to move by sliding in a vertical plane, that is to say parallel to the direction Z indicated in this figure.
• the hood H comprises a counterweight system, comprising in the example shown a counterweight 11 connected by a main cable 7a to two secondary cables 7b, 7c passing over two return pulleys 9a, 9b and connected to the window 5.
• the counterweight 11 has a slightly lower weight than that of the window 5, so as to avoid the sudden fall of the latter when it is closed, and to facilitate its opening by a laboratory worker.
• the hood H also comprises a braking device according to the invention, mounted in the upper part of the enclosure 3, comprising a magnetic compensator 31 and a belt 15 passing in a loop over two braking pulleys 17a, 17b.
• a bridging member 19 fixedly connects a strand of the belt 15 to the main cable 7a.
• a ribbon potentiometer 21 housed inside enclosure 3 and connected to window 5 enables the vertical position of this window to be detected at any time.
• Such a detection barrier 23 is chosen so as to detect on the fly the passage of bodies from the inside to the outside of the volume of the enclosure 3, through the opening released by the window 5.
• the braking device, the potentiometer 21, the detection barrier 23, the switch 27 are connected to an electronic supervision box 29, this box being able to be integral with the hood H, or else located at a distance from it. ci, and connected by wires or by radio.
• the braking device comprises the magnetic compensator 31 strictly speaking, the notched braking pulley 17a cooperating with this magnetic compensator, and the toothed belt 15 passing over this pulley and over the other toothed pulley
• This braking device further comprises support means, comprising on the one hand a base 35 and on the other hand a bracket 37 intended to be fixed on this base.
• the bracket 37 has holes 38 and notches 39a, 39b, 39c, 39d on several of its faces.
• the toothed braking pulley 17a is pivotally mounted around a pulley bolt 40 secured to the base 35.
• the magnetic compensator 31 is mounted fixed on the bracket 37 by means of a magnetic compensator bolt 41 which passes through it.
• this magnetic compensator comprises:
• first brake disc 47 made of steel, of substantially circular shape, crossed in its center by the magnetic compensator bolt 41, mounted fixed in rotation and free in translation thereon,
• a brake shoe 49 made of Ferrodo ® type material or the like, of substantially circular shape, crossed in its center by the magnetic compensator bolt 41, mounted free in rotation and in translation on the latter, and
• FIG. 5 shows the magnetic compensator 31 when it is in the released configuration (“disengaged” compensator): in this configuration, the electromagnet 45 is electrically powered, which has the effect of pressing the first brake disc 47 against this electromagnet, against the thrust exerted by the spring 48. In this configuration, no axial force is therefore exerted by the first brake disc 47 on the brake pad 49, which itself therefore exerts no frictional force on the second brake disc 51.
• the brake disc 51 and the notched pulley 17a can therefore rotate freely around the pulley bolt 40, under the action of the sole weight of the window 5.
• the magnetic compensator 31 when it is in the braked configuration (“engaged” compensator): in this configuration, the electromagnet 45 is not electrically powered, so that the spring exerts a force having the effect of pressing the first brake disc 47 against the brake pad 49, itself pressed against the second brake disc 51.
• the brake pad 49 is sandwiched rubbing between the two brake discs 47 and 51, having the effect to block by friction the rotation of the brake disc 51 and therefore of the notched pulley 17a.
• the magnetic compensator 31 and the notched pulley 17a are mounted inside the base 35 and the stirrup 37, so that the axis Al of rotation of the pulley is substantially perpendicular to the plane of the wall 54: the toothed belt 15 passes inside the notch 39c of the stirrup 37, and the orifice 38 of the stirrup remains free.
• the stirrup 37 is fixed directly to the wall 54, and the axis of rotation A2 of the pulley is substantially parallel to the plane of the wall 54: the toothed belt 15 passes to inside the notch 39a of the caliper 37, and the brake bolt 41 passes through the hole 38 of this caliper.
• one of the strands of the toothed belt 15 therefore moves perpendicular to the plane of the wall 54.
• the detection barrier 23 detects the presence of the laboratory worker, and the supervision box 29 maintains the absence of electrical power to the electromagnet. 45, so as to maintain the magnetic compensator 31 in the braking configuration, preventing the rotation of the toothed pulley 17a.
• the toothed belt 15 is therefore itself blocked, which has the effect of also blocking the main cable 7a of the counterweight system, via the bridging member 19.
• the supervision box 29 orders the electrical supply of the electromagnet 45, so as to place the magnetic compensator 31 in the released configuration, allowing controlled rotation of the notched pulley 17a, under the effect of the weight of the window 5.
• This window therefore descends gently towards its closed position of the enclosure 3 of the hood H.
• the intrusion detection barrier 23 sends a signal to the box supervisor 29, so that it again cuts off the electrical supply to the electromagnet 45 of the magnetic compensator 31, in order to block the lowering movement of the window 5.
• the window 5 can therefore descend under the effect of its weight as far as the bench 1, and completely close the interior volume of the enclosure 3.
• a servomotor can be provided to adapt the height of the window 5 to the desired air extraction rate.
• the attempt to lift the window 5 by the laboratory worker can be detected by the ribbon potentiometer 21, which then sends a signal to the supervision box 29, which then triggers the power supply to the electromagnet 45, allowing the magnetic compensator 31 to be disengaged.
• the ribbon potentiometer 21 detects a start of lowering movement of the window, and then sends a signal to the supervision box 29 which then stops the power supply to the electromagnet 45, making it possible to replace the magnetic compensator 31 in the braking configuration.
• the braking device according to the invention is of the “fail safe” type, that is to say that by lack of electrical supply to the electromagnet 45, it performs the braking of the window 5. [0071] Such a braking device is therefore very safe, and consumes little electrical energy since only the occasional cases of disengagement of the magnetic compensator 31 require a power supply from the electromagnet 45.
• this braking device makes this braking device suitable both for new hoods and for reconditioned hoods, in which all sorts of geometries of the counterweight system can be used.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Ventilation (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=76845254

Family Applications (1)

Country Status (2)

Family Cites Families (8)

• 2021
  • 2021-06-11 WO PCT/FR2021/051052 patent/WO2022258889A1/fr active Application Filing
  • 2021-06-11 EP EP21739744.7A patent/EP4351810A1/de active Pending

Also Published As

Similar Documents

Legal Events