DE102006027585B4 - Hinge-mounted safety device for automatic systems and machines - Google Patents

Abstract

Hinged safety device for automatic systems and machines, comprising: - a fixed element (4) which can be anchored to a fixed part (S) of a machine or system and which defines a first axis (X); - At least one movable element (2) that can be anchored to a protective plate or door (P) of the machine or system; - Hinge means (7) for rotatably connecting the fixed element (4) and the at least one movable element (2) about a second axis (W); - At least one fixed electrical contact (6 ') which is mounted within the fixed element (4) and at least one movable electrical contact (6) along the first axis (X) in order to open and close a respective circuit (5) Effect supply to the machine or system; - Means (8) for converting the rotary movement (w) of the at least one movable element (2) into a translational movement (x) of the movable contact (6) ...

Description

field of use

The present invention finds application in the field of electrical safety devices and more particularly relates to a hinged safety device for automatic equipment and machines of the type described in the preamble of claim 1.

State of the art

It is well-known that automatic installations and workplaces equipped with dangerous moving parts or using dangerous substances, in particular irritating liquids, require suitable protective devices to prevent the operators responsible for the different positions of the workstation from even having to do so suffer serious damage.

For these purposes, the installations have protection plates arranged along their own circumference, which provide a barrier between the operators and the hazardous components, thereby preventing accidental contact with moving parts or hazardous substances. The panels are provided with appropriate safety devices which will bring the whole system and / or the particular section to a standstill if accidentally or intentionally opened by an operator having to carry out repair or calibration operations of the various components of one or more parts of the worksite , These devices consist of safety switches which are mounted on the frame of the protective device or are mounted on the hinges with which the connection between the plate and the frame of the machine is made. In the latter case, furthermore, the switches may be located inside the hinge or mounted on the mounting post of the hinge on the support frame of the structure.

The switches mounted directly on the protector make use of an actuator which interacts with the electrical contacts during the opening and closing of the protector, thereby engaging and disengaging into a gap provided thereon, which is formed on the housing of the switch. These movements correspond to the opening and closing of the electrical contacts and, consequently, the switching on and off of the system at a predetermined point of engagement, which corresponds to a minimum opening angle of the plate.

However, these known solutions undoubtedly have the disadvantage of requiring more accurate settings both during installation and during use of the system. Namely, these devices are extremely sensitive to the wear caused by the continuous opening and closing movement of the plates, whereby displacement of the actuator relative to the slot occurs. In addition, the entrance slot of the actuator tends to be slightly contaminated, so these solutions are unsuitable for use on food processing equipment.

Alternative solutions where the switches are out of hinge use the pivot of the hinge as the actuator on which the switch is mounted. It is thus exploited the rotation of the pin to cause the opening of the contacts and consequently the stoppage of the plant

The disadvantage of these solutions, however, is that the safety hinges thus produced have a complex installation and require the replacement or modification of the pin of the previously existing hinge. Therefore, the installation times are necessarily long and the installation costs high. Furthermore, they do not solve the problem that the internal adjustment of the contacts is still required to determine the point of engagement of the device.

In addition, other solutions have contacts arranged on the actuator, which are not active at the same time and thus cause difficulties in determining the point of engagement. Namely, it is known that the switches of this type have a plurality of fixed contacts which, by connection to respective movable contacts, interact to selectively close suitable circuits. For each circuit that you want to open or close, four fixed contacts and four moving contacts can be used. In this way, the likelihood of failure of the safety device due to a possible sticking of a movable contact to the respective fixed contact or due to the deposition of external particles between the contacts themselves is reduced. A disadvantage of these known solutions is undoubtedly that the dimensional, shape and position tolerances of the movable contacts and the fixed contacts can significantly reduce the adhesive areas between the movable and the fixed contacts, whereby problems occur in the flow of electric current. In addition, the wear of the contacts can lead to a rapid degradation of the contact areas and thus require frequent replacement.

Out EP 1 239 496 B1 For example, there is known a safety hinge having an engagement point adjustment device comprising a pin which transmits its own rotational movement to the actuator of the circuit by a motion translation lever system which converts the rotation of the hinge into a linear movement of the electrical contacts.

However, this solution has the disadvantage of comprising a lever mechanism for converting the rotational movement of the guard movement into a rectilinear movement of the actuator, which consists of numerous elements which are connected together with little play. This results in a strong susceptibility to wear, which can thus quickly lead to incorrect operation of the entire device. The latter will therefore not have a consistent point of engagement during the period of its mechanical life and will require periodic adjustment and calibration interventions. Consequently, in the wrong setting, the replacement of the entire hinge is necessary. Another limitation of this solution is that the maximum opening of the hinge must not exceed 180 °,

Out DE 93 18 787 U1 respectively. US Pat. No. 4,049,934 a device according to the preamble of claim 1 is known.

Out US 4 066 857 A a hinged safety device for automated systems and machines is known in which the activation angle of the electrical contacts by adjusting the position of the hinge pins is adjustable.

Presentation of the invention

The object of the present invention is to obviate the above-mentioned drawbacks by providing a hinged safety device for automatic equipment and machines which has less wear and stable guidance at its moving parts.

A particular object is to provide a hinged safety device that allows transmission of the movement of the guards to the circuits in an extremely simple manner and with a small number of components.

A further object is to provide a safety device that saves space and has a high resistance to wear of the various components that adjust the operation of the electrical contacts, while it is extremely accurate and secure and ensures an unimpaired during their entire life.

Another object of the present invention is to provide a device which allows easy and immediate adjustment of the point of engagement and allows further adjustments even after sealing, while still being safe.

Last but not least, another object is to provide a device that is durable and compact, prevents internal buildup of work debris or other contaminants, and that, finally, is easy to clean.

These objects and other objects, which will be more apparent below, are achieved by a hinged safety device according to claim 1.

Thanks to the particular configuration claimed, the device according to the invention allows a direct connection between the anchoring element on the plate and the activating means of the electrical contacts, without the interposition of lever systems or other motion reversal or motion transmission mechanisms, which is therefore simple and with a small number of components undoubtedly give economic benefits. The motion conversion means and the hinge means are on the same axis, thereby saving space.

According to the invention, the translationally displaceable part of the motion conversion means has a prism-shaped body, which is preferably slidably mounted and which is rotatably locked within an axial seat of prismatic complementary form within the fixed element.

Advantageously, a slide may be provided which is slidably mounted within the fixed member along the first axis and is operatively connected to the movable contact to cause the opening / closing of the corresponding circuit. The slider has an exposed end which abuts against the prismatic body to translate from the latter during rotation of the pin.

Thanks to this particular embodiment of the invention, a space-saving device is provided. Further, the cam connection enables activation of the contacts with a high wear resistance of the various operation regulating components, thereby providing a highly accurate and safe Operation of the device and an unchanged point of engagement throughout the life of the same is guaranteed.

Advantageously, the device may comprise an adjusting screw screwed into a bore of the prismatic body to micrometrically adjust the opening / closing position of the movable contact relative to the corresponding fixed contact. Further, the pin may have an axial through recess which is aligned with the adjustment screw to allow access from the outside.

Thanks to this last feature, the device according to the invention allows an easy and immediate adjustment of the own point of engagement and at the same time permits further adjustments even after the sealing, nevertheless it is safe against any negligent action.

Advantageously, the box-shaped element can be equipped with optical LED reporting means on its own outer surface. In this way, a safety device is provided, which, in addition to a robust and compact structure for preventing deposits of working residues or other contaminants in its interior, finally also allows an immediate message in case of incorrect operation.

Brief description of the drawings

Other features and advantages of the invention will become more apparent from the detailed description of a preferred but not exclusive embodiment of a hinged safety device according to the invention, shown by way of example and not limitation with reference to the accompanying drawings, in which:

1 is a view of a particular application of the device according to the invention in a work station;

2 a partially exploded view of a safety device according to the invention represents;

3 a partial sectional view of the device 2 according to the level of lane II in a first operating configuration;

4 a top view 3 is;

5 a partial sectional view of the device 2 according to the level of lane II in a second operating configuration;

6 a top view 5 illustrated;

7 a perspective view of a first detail 2 is;

8th a front view of a first detail 7 represents;

9 a plan view of a second detail 7 illustrated;

10 a sectional view of another detail 2 represents;

11 an assembled view of the device according to the invention in a first embodiment illustrated;

12 represents an assembled view of the device according to the invention in a second embodiment.

Detailed description of a preferred embodiment

With reference to the above drawings, the invention may be generally denoted by reference numerals 1 characterized apparatus are a hinged safety device on accident protection plates for an automatic work system or a part thereof as in 1 shown application can be found.

In accordance with the invention, the safety device on a crash plate P by a movable element 2 attached by conventional anchoring means such as screws or bolts that fit into the element 2 trained seats 3 can engage, is attached to the plate P. The attachment of the entire device 1 on the supporting component S of the automatic machine or system, however, takes place through the solid box-shaped element 4 that is part of the components of the device 1 contains. The solid element 4 is made of metallic material or the like, in any case it has suitable resistance properties for supporting the load of the plate P.

Turning the device on and off 1 occurs in each case by opening and closing one or more circuits 5 , each one with a respective pair of contacts 6 . 6 ' connected within the solid box-shaped element 4 are included and of which at least one along a first longitudinal axis X is movable.

The solid element 4 is in turn by hinge means 7 with the moving element 2 rotatably connected about a second axis W.

So they are means of transformation 8th the rotational movement of the movable element 2 about the second axis W in the translational movement of the means of the movable contact 6 along the first axis X present.

The conversion means 9 Namely comprise a relative to the second axis W rotatable part 9 and a relative to the second axis W parallel translationally displaceable part 10 ,

A particular feature of the invention is represented by the fact that the first axis X along the translation movement x of the movable electrical contacts 6 takes place, is substantially parallel or coincident with the second axis W, on the other hand, the rotation w of the anchoring element 2 takes place.

Furthermore, there is the translationally displaceable part 10 with the hinge means 7 directly associated with no motion reversal or motion transmission mechanisms such as Helbelsysteme or similar systems are interposed.

The hinge means 7 transfer the movement over a pair of arms 11 . 11 ' that comes from the moving element 2 project in a transverse direction Y and on corresponding cylindrical seats 12 . 12 ' support that at the axial ends 13 . 13 ' of the solid element 4 are formed. The poor 11 . 11 ' become integral with the moving element 2 produced.

As in particular in the figures of 3 to 6 represented corresponds to the rotation Ø of the movable anchoring part 2 opposite the fixed element 4 , and so with respect to the system, the same rotation Ø 'of the rotatable part 9 the motion conversion tool 8th ,

The rotatable part 9 consists of a substantially cylindrical pivot 14 by being inserted in the first cylindrical seat 12 of the arm 11 on the moving part 2 can be determined.

To the connection between the pin 14 and the associated seat 12 make a gun 15 and a sealing ring 16 provided coaxial with the pin 14 are attached. The rifle 15 is self-lubricating type and made of plastic.

To ensure proper connection of the two parts and to prevent relative rotational sliding, the arm points 11 a transverse through-hole 17 for inserting a retaining pin 18 on top, with one on the side outer surface 20 of the pin 14 trained seat 19 engaged.

The pivot 14 therefore stands with the corresponding translationally displaceable part 10 in interaction, on the other hand, from a prismatic body 21 consisting within a formed inside the solid element and a complementary shape to the prismatic body 21 having axial seat 22 is slidably mounted.

To the connection between the prismatic body 21 and the axial seat 22 to ensure the prism-shaped body 21 at each of its transverse ends 23 . 23 ' a longitudinal pair of guides 24 . 24 ' on that with corresponding on the inner side surface 26 of the solid element 4 trained guide channels 25 . 25 ' engage. In this way, the prism-shaped body 21 forced to move along the first axis X only by translation x.

The connection between the pin 14 and the prism-shaped body by means of Plankurvenmittel (Plannockenmittel) 27 , As in the figures of 7 to 9 shown include the means 27 an annular part 28 that with one of the exposed axial ends 29 of the pin 14 coaxial and firmly connected. The annular part 28 is with an axial pair of protrusions 30 . 30 ' equipped, which are diametrically opposed and each have a pair of pressure surfaces 31 have opposite inclination with respect to an axial diametrical plane a and pass through the second axis W. The projections 30 . 30 ' stand by the pressure surfaces 31 with each on an apparent annular part 33 of the prismatic body 21 formed axial recesses 32 . 32 ' in interaction. Both recess 32 . 32 ' have a pair of pressure ramps 34 , which are opposite and have a slope, that of the mutual pressure surfaces 31 so that they can engage with or be freed from the latter.

Both the printing surfaces 31 as well as the respective ramps 34 have a sufficiently pronounced transversal configuration to provide a steady connection and hence a steady operation for the motion conversion means 8th even with a strong degree of wear caused by a long period of use of the device 1 is conditional to ensure. Preferably, furthermore, the recesses 32 . 32 ' and the respective axial protrusions 30 . 30 ' different development sheets d, d 'to allow a unique connection. In this way, namely the device 1 resume the initial position only after a full 360 degree turn, ensuring unambiguous operation and consequently greater safety.

The of the rotation Ø of the protective plate P by means of the anchoring element 2 induced rotation Ø 'of the pin 14 causes the pressure on the prismatic body 21 which move translationally by blocking the rotation and thus to a substantially longitudinal slide 35 will act. The latter is inside a housing 36 that is in the solid box-shaped element 4 located and also the contacts 6 . 6 ' contains, sliding stored. Further, the slider 35 with the moving electrical contacts 6 operatively connected and therefore he becomes the circuits 5 activate, with the moving contacts 6 with the respective fixed contacts 6 ' get connected.

The slider 35 has an exposed end 37 up against the prismatic body 21 strikes. At rotation Ø of the moving part 2 , become the motion transformation means 8th hence the translation movement x of the movable electrical contacts 6 by means of the parallel movement of the slider 35 which translates in response thereto along the first axis X translational. How out 10 the slider is visible 35 in this way, because it attaches to the moving contacts 6 is set, this entrain while keeping in touch with each inside the case 36 contained solid electrical contacts 6 ' or cause a separation of the same, the supply circuits 5 closed or opened at the machine or plant.

In accordance with the preferred but not exclusive embodiment of the invention illustrated in the accompanying drawings, there are four pairs of electrical contacts 6 . 6 ' existing, which operate at the same time recruitment requirements, so that the intervention security is increased. Every moving contact 6 also comes with a single firm contact 6 according to a one-to-one association. In this way, a first circuit with a logic control unit z. B. a PLC and two other pairs of contacts regulate the communicating with a security module circuits.

A last circuit finally remains free for connection to any other equipment of the system such as a warning lamp for the operating state of the plates. The presence of multiple contacts ensures greater safety for the system and allows it to comply with industry-specific safety regulations.

To the ongoing connection between the slider 35 and the prismatic body 21 To ensure are advantageous elastic counteracting elements 38 , essentially one inside the case 36 attached coil spring, present on the slider 35 and act against the prismatic body 21 to force.

The translation required to make this connection represents the function of the point of engagement, which is referred to as the minimum angle of rotation necessary for activation of the system 1 by opening the circuits 5 he follows. The point of intervention must be during the installation of the device 1 be preset. Its calibration is done by means of an adjusting screw 40 for adjusting the initial distance of the slider 35 from the prismatic body 21 , The screw 40 is by screwing in one within the prismatic body 21 axially formed threaded hole 41 added. The adjustment of the screw 34 takes place in a very simple manner from above through an axial through recess 42 on the tang 14 is formed, and a seal closure 43 can be set up to prevent negligence.

The motion transformation means 8th , the hinge means 7 and the case 36 are inside the solid box-shaped element 4 contain. The solid element 4 is also compact and is possible recesses or holes exclusively on the wall 44 which is intended to be mounted on the supporting member S. In this way, the formation of any contamination due to the processing or the external environment is not possible, so the device is also suitable for use in food processing plants. The wall 44 If necessary, by one with simple screws 45 connectable to be opened lid, which is the opening of the fixed element 4 facilitated for possible maintenance or cleaning operations.

Furthermore, the second cylindrical seat allows 12 ' of the solid element 4 extending longitudinally opposite to the first seat 12 lies the passage of the support cable 46 of the circuits 5 or an electrical connector. This second seat 12 ' can both on a bottom wall 47 as in 11 shown or on the wall 44 as in 12 be designed illustrated and thereby preserve the aesthetics of the machine.

In 11 also become optical reporting devices 48 to control the correct operation of the device 1 shown, for example, by one on the outside surface 49 of the solid element 4 attached LED can be displayed. The LED 48 makes it possible to dispense with an external tester, which is used to check the point of contact during its setting in the installation phase with the contacts 6 . 6 ' to be connected in series.

From the foregoing description, it will be apparent that the invention achieves the stated objects by providing a hinged safety device that allows movement transfer from the protection devices to the circuits in a very simple manner and with a small number of components.

In addition, thanks to the particular design of the motion conversion means, a space-saving device with a high resistance to wear of the various components which regulate the actuation of the electrical contacts is provided. The device is therefore extremely accurate and safe.

The device according to the invention may be the subject of numerous variations and variants, all of which fall within the inventive concept set forth in the appended claims. All details may be replaced by other technically equivalent elements and the materials may be of a different nature as needed without departing from the scope of the invention.

Even though the device has been particularly described with reference to the accompanying drawings, the reference numerals used in the specification and claims are intended to enhance the understanding of the invention and are in no way to be construed as limiting the scope of the claimed protection.

Claims (12)

Hinge-mounted safety device for automated equipment and machines comprising: - a fixed element ( 4 ), which can be anchored to a fixed part (S) of a machine or plant, and which determines a first axis (X); At least one movable element ( 2 ) which can be anchored to a protective plate or door (P) of the machine or equipment; - hinge means ( 7 ) to the solid element ( 4 ) and the at least one movable element ( 2 ) to rotatably connect to a second axis (W); At least one fixed electrical contact ( 6 ' ), which within the solid element ( 4 ) and at least one movable electrical contact ( 6 ) along the first axis (X) to open and close a respective circuit ( 5 ) to supply the machine or plant; - Medium ( 8th ) for converting the rotational movement (w) of the at least one movable element ( 2 ) in a translational movement (x) of the movable contact ( 6 ) along the first axis (X), wherein the motion conversion means ( 8th ) a rotatable part ( 9 ) and a translationally displaceable part ( 10 ) with respect to the second axis (W); wherein the first axis (X) is substantially parallel or coincident with the second axis (W), the translationally displaceable part (X) 10 ) of the motion conversion means ( 8th ) with the hinge means ( 7 ) without intervening motion reversal or motion transmission mechanisms, wherein the motion conversion means ( 8th ) Plane curve means ( 27 ) having at least one axial projection ( 30 ), which with the rotatable part ( 9 ), and the at least one axial recess ( 32 ), which with the translationally displaceable part ( 10 ), wherein the rotatable part ( 9 ) a pivot ( 14 ) and the translationally displaceable part ( 10 ) a body ( 21 ), wherein the at least one axial projection ( 30 ) at least one inclined pressure surface ( 31 ) and the at least one axial recess ( 32 ) at least one pressure ramp ( 34 ), wherein the inclined pressure surface ( 31 ) and the pressure ramp ( 34 ) are directed towards each other so as to cooperate, so that the removal or approach of the translationally displaceable part ( 10 ) opposite the rotatable part ( 9 ) in response to a relative rotation (Ø) of the movable element ( 2 ) with respect to the solid box-shaped element ( 4 ), characterized in that the fixed element ( 4 ) is box-shaped, and that the body ( 21 ) is prism-shaped, wherein the at least one projection ( 30 ) and the at least one recess ( 32 ) to respective substantially annular coaxial parts ( 28 . 33 ) of the pivot ( 14 ) and the prism-shaped body ( 21 ), wherein the inclined pressure surface ( 31 ) and the pressure ramp ( 34 ) have a sufficiently pronounced transverse configuration in order to ensure a continuous connection even with a high degree of wear, and wherein the hinge means ( 7 ) at least one pair of arms ( 11 . 11 ' ) formed from the at least one movable element ( 2 ) and on the solid element ( 4 ), at its axial ends ( 13 . 13 ' ) supported. Device according to claim 1, characterized in that the pivot ( 14 ) on one of the arms ( 11 ) and in an im Essentially cylindrical first seat ( 12 ) of an axial end ( 13 ) of the solid element ( 4 ) is inserted rotatably. Device according to claim 1, characterized in that the at least one axial projection ( 30 ) at an exposed end ( 29 ) of the pivot ( 14 ) is trained. Device according to claim 1, characterized in that the prismatic body ( 21 ) is slidably mounted and in an axial seat ( 22 ) prismatic complementary form in the solid element ( 4 ) is rotatably locked. Device according to claim 4, characterized in that the at least one pressure ramp ( 34 ) on the prism-shaped body ( 21 ) is trained. Device according to claim 1, characterized in that it comprises a pair of projections ( 30 . 30 ' ) and a pair of recesses ( 32 . 32 ' ), both of which each have a pair of surfaces ( 31 ) and a pair of pressure ramps ( 34 ) with opposite inclinations to an axial diametral plane (a) passing through the second axis (W). Device according to claim 1, characterized in that it comprises a slider ( 35 ), which within the solid element ( 4 ) is slidably mounted along the first axis (X), wherein the slider ( 35 ) with the at least one movable contact ( 6 ) is operatively connected to open / close a corresponding circuit ( 5 ). Device according to claim 7, characterized in that the slide ( 35 ) an exposed end ( 37 ), which against the prism-shaped body ( 21 ) is in abutment with respect to the latter in the rotation (Ø ') of the pin ( 14 ) translationally displaced, wherein elastic counteracting elements ( 38 ) are provided on the slide ( 35 ), to be free ( 37 ) normally with the prismatic body ( 21 ) to maintain contact. Device according to claim 4, characterized in that it comprises an adjusting screw ( 40 ), which in a threaded internally bore ( 41 ) of the prismatic body ( 21 ) is screwed to the opening / closing position of the at least one movable contact ( 6 ) against a corresponding fixed contact ( 6 ' ) micrometrically adjust. Device according to claim 9, characterized in that the pin ( 14 ) an axial through recess ( 42 ), which with the adjusting screw ( 40 ) to allow access from the outside. Device according to claim 7, characterized in that it comprises a plurality of fixed electrical contacts ( 6 ' ) and on movable electrical contacts ( 6 ) contained in a housing ( 36 ), which is intended to move the slider ( 35 ) Sliding. Device according to claim 1, characterized in that the solid box-shaped element ( 4 ) optical LED reporting means ( 48 ) located on the outer surface ( 49 ) of the solid element ( 4 ) are mounted.

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