CH636581A5

CH636581A5 - Pantograph lifting platform

Info

Publication number: CH636581A5
Application number: CH1073579A
Authority: CH
Inventors: Eride Rossato
Original assignee: Eride Rossato
Priority date: 1978-12-07
Filing date: 1979-12-04
Publication date: 1983-06-15
Also published as: FR2443420A1; BE880488A; IT1107387B; FR2443420B1; IT7841678A0; DE2948909A1

Description

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RIVENDICAZIONI

1. Ponte sollevatore a pantografo, particolarmente per automezzi, comprendente una coppia di corsie (4,4'), sostenute ciascuna da una coppia di montanti (2, 3, 2', 3') a loro volta articolati a due longheroni (1,1') appoggiati al pavimento, caratterizzato dal fatto che i montanti omologhi 1. Scissor lift bridge, particularly for motor vehicles, comprising a pair of lanes (4,4 '), each supported by a pair of uprights (2, 3, 2', 3 ') which are in turn articulated with two side members (1 , 1 ') resting on the floor, characterized in that the homologous uprights

(2, 2' e/o 3, 3') di almeno una coppia sono tra loro collegati a terra attraverso una barra di torsione (5). (2, 2 'and / or 3, 3') of at least one pair are connected to each other via a torsion bar (5).

2. Ponte sollevatore secondo la rivendicazione 1, caratterizzato dal fatto di essere provvisto di una coppia di martinetti oleodinamici (14) a semplice effetto disposti tra ciascuna corsia (4, 4') ed il corrispondente montante (2,2', 3, 3'). Lifting platform according to claim 1, characterized in that it is provided with a pair of single-acting hydraulic jacks (14) arranged between each lane (4, 4 ') and the corresponding upright (2,2', 3, 3 ').

3. Ponte sollevatore secondo la rivendicazione 2, in cui una sola coppia di montanti (3, 3') sono collegati da una barra di torsione (5), caratterizzato dal fatto che i martinetti oleodinamici (14) sono disposti tra ciascuna corsia (4,4') ed il corrispondente montante (2, 2') non interessato dalla barra di torsione (5). Lifting bridge according to claim 2, wherein a single pair of uprights (3, 3 ') are connected by a torsion bar (5), characterized in that the hydraulic jacks (14) are arranged between each lane (4 , 4 ') and the corresponding upright (2, 2') not affected by the torsion bar (5).

4. Ponte sollevatore secondo la rivendicazione 3, caratterizzato dal fatto che il punto di articolazione di ciascun martinetto oleodinamico (14) alla relativa corsia (4, 4') cade internamente ai punti di articolazione dei due montanti (2, 3, 2', 3') alla corsia stessa. Lifting platform according to claim 3, characterized in that the point of articulation of each hydraulic jack (14) to the relative lane (4, 4 ') falls inside the points of articulation of the two uprights (2, 3, 2', 3 ') to the lane itself.

5. Ponte sollevatore secondo la rivendicazione 1, caratterizzato dal fatto che la barra di torsione (5) è ricoperta da una pedana (6). Lifting platform according to claim 1, characterized in that the torsion bar (5) is covered by a platform (6).

6. Ponte sollevatore secondo la rivendicazione 1, caratterizzato dal fatto di essere provvisto di piani inclinati (8) di raccordo tra le corsie (4, 4') abbassate ed il pavimento, Lifting platform according to claim 1, characterized in that it is provided with inclined planes (8) for the connection between the lowered aisles (4, 4 ') and the floor,

detti piani inclinati essendo provvisti di cinematismi atti a provocare il loro ripiegamento automatico mano a mano che le corsie (4, 4') si sollevano. said inclined planes being provided with kinematic mechanisms capable of causing their automatic folding as the lanes (4, 4 ') rise.

7. Ponte sollevatore secondo la rivendicazione 6, caratterizzato dal fatto che ciascun piano inclinato (8) è articolato alla corrispondente corsia (4, 4') e comprende due porzioni (9, 10) reciprocamente articolate tra loro e collegate da un sistema di leve azionato da un'asta (11) collegata ad un montante (3, 3') in un punto diverso dal punto di articolazione di quel montante alla corsia (4, 4'). Lifting platform according to claim 6, characterized in that each inclined plane (8) is articulated to the corresponding lane (4, 4 ') and comprises two portions (9, 10) mutually articulated together and connected by a system of levers operated by a rod (11) connected to an upright (3, 3 ') at a point other than the point of articulation of that upright to the lane (4, 4').

8. Ponte sollevatore secondo la rivendicazione 1, caratterizzato dal fatto di essere provvisto all'ingresso di ciascun martinetto (14) di una valvola di blocco (19) agente nel senso di impedire la fuoriuscita del fluido operativo dal martinetto stesso (14) quando la differenza di pressione tra l'interno e l'esterno di questo supera un prefissato valore. 8. Lifting bridge according to claim 1, characterized in that it is provided at the inlet of each jack (14) with a block valve (19) acting in the sense of preventing the operating fluid from leaking out of the jack (14) when the pressure difference between the inside and the outside of this exceeds a predetermined value.

9. Ponte sollevatore secondo la rivendicazione 8, caratterizzato dal fatto di essere provvisto, in corrispondenza di ciascun martinetto di sollevamento (14), di un arpionismo di ritegno comprendente una slitta dentata mobile (22) ed un nottolino (23) con essa cooperante, la dentatura della slitta essendo tale da consentire il sollevamento del ponte e da contrastarne l'abbassamento. 9. Lifting bridge according to claim 8, characterized in that it is provided, in correspondence with each lifting jack (14), with a retaining harpoon comprising a mobile toothed slide (22) and a pawl (23) cooperating with it, the toothing of the slide being such as to allow the lifting of the bridge and to counteract its lowering.

10. Ponte sollevatore secondo la rivendicazione 9, caratterizzato dal fatto che la slitta mobile è costituita da un organo (20) articolato alla corrispondente corsia (4, 4') in prossimità del martinetto di sollevamento (14) e provvisto di una porzione dentata (22) e di una massa (21) agente per gravità nel senso di mantenere la porzione dentata (22) impegnata con il bordo (23) di detto martinetto, mezzi essendo previsti per disimpegnare detta porzione dentata dal bordo (23) di detto martinetto di sollevamento (14). Lifting platform according to claim 9, characterized in that the mobile slide is constituted by an element (20) articulated to the corresponding lane (4, 4 ') near the lifting jack (14) and provided with a toothed portion ( 22) and of a mass (21) acting by gravity in the sense of keeping the toothed portion (22) engaged with the edge (23) of said jack, means being provided for disengaging said toothed portion from the edge (23) of said jack lifting (14).

11. Ponte sollevatore secondo la rivendicazione 10, caratterizzato dal fatto di comprendere un martinetto oleodinamico (25) agente sulla massa (21) per disimpegnare la porzione dentata (22) dal bordo (23) del martinetto di sollevamento (14), detto martinetto (25) essendo provvisto di una molla per il ritorno elastico in posizione di riposo. Lifting bridge according to claim 10, characterized in that it comprises a hydraulic jack (25) acting on the mass (21) to disengage the toothed portion (22) from the edge (23) of the lifting jack (14), called jack ( 25) being provided with a spring for the elastic return in the rest position.

La presente invenzione concerne un ponte sollevatore a pantografo, particolarmente per automezzi. The present invention relates to a scissor lift bridge, particularly for motor vehicles.

Sono noti ponti sollevatori impiegati nelle autofficine, carrozzerie, ecc. Essi comprendono due longheroni paralleli o corsie, sulle quali si fa salire l'automezzo, essendo dette corsie sollevabili per consentre un comodo accesso alla parte inferiore dell'automezzo stesso. Lifting platforms used in car repair shops, body shops, etc. are known. They comprise two parallel side members or lanes, on which the vehicle is raised, being said lanes that can be raised to allow convenient access to the lower part of the vehicle itself.

Il sollevamento delle corsie può avvenire con diversi sistemi, meccanico, oleodinamico, ecc., e diversi modelli sono ormai presenti sul mercato. Tra questi ha trovato particolare diffusione attualmente un tipo denominato «a pantografo», nel quale ogni corsia è articolata a due montanti a loro volta articolati ad un longherone appoggiato al pavimento e formanti complessivamente un parallelogramma articolato. The lifting of the aisles can take place with different systems, mechanical, hydraulic, etc., and different models are now on the market. Among these, a type called "pantograph" has found particular diffusion, in which each lane is articulated with two uprights in turn articulated to a longitudinal member resting on the floor and forming an articulated parallelogram as a whole.

I vantaggi di tale soluzione consistono in un limitato ingombro del ponte in condizione abbassata, e nella facilità di realizzare il movimento del parallelogramma articolato con sistemi oleodinamici. The advantages of this solution consist in a limited size of the bridge in the lowered condition, and in the ease of carrying out the movement of the articulated parallelogram with hydraulic systems.

Allo scopo di evitare che le due corsie possano sollevarsi in modo differente è noto di collegarle con robusti traversi, formanti con queste praticamente una piattaforma che si solleva appoggiata sui quattro montanti (due per lato). In order to prevent the two aisles from rising differently, it is known to connect them with sturdy cross beams, practically forming a platform with these which lifts resting on the four uprights (two on each side).

Un inconveniente di questi noti ponti sollevatori a pantografo consiste nel fatto che i traversi, durante il pratico impiego del ponte, sono di intralcio ai movimenti degli operai e schermano parzialmente l'automezzo impedendo, o comunque rendendo difficoltoso l'accesso alle parti schermate. A drawback of these known scissor lift bridges consists in the fact that the cross beams, during the practical use of the bridge, hinder the movements of the workers and partially shield the vehicle preventing, or in any case making access to the shielded parts difficult.

Un altro inconveniente consiste nel fatto che nel caso sia richiesto un carrello trasversale mobile lungo le corsie e provvisto di martinetto per l'ulteriore sollevamento del veicolo o di parti di questo rispetto alle corsie, i traversi sono di ostacolo al movimento del carrello ed impongono pertanto soluzioni complesse, costose e di non semplice realizzazione ed impiego. Another drawback consists in the fact that if a transversal trolley is required along the lanes and equipped with a jack for the further lifting of the vehicle or parts thereof with respect to the lanes, the crosspieces are an obstacle to the movement of the trolley and therefore require complex, expensive and not easy to manufacture and use solutions.

Secondo l'invenzione il problema è risolto con un ponte sollevatore a pantografo, particolarmente per automezzi, comprendente una coppia di corsie sostenute ciascuna da una coppia di montanti a loro volta articolati a due longheroni appoggiati al pavimento, caratterizzato dal fatto che i montanti omologhi di almeno una coppia sono tra loro collegati a terra attraverso una barra di torsione. According to the invention, the problem is solved with a scissor lift, particularly for motor vehicles, comprising a pair of lanes each supported by a pair of uprights in turn articulated with two side members resting on the floor, characterized in that the homologous uprights of at least one pair are connected to each other via a torsion bar.

II ponte secondo l'invenzione offre il vantaggio di eliminare qualsiasi collegamento diretto tra le due corsie, e di non creare pertanto alcun ostacolo agli operai che lavorano sotto l'automezzo sollevato né ad un eventuale carrello trasversale mobile per tutta la lunghezza delle corsie. Inoltre la barra di torsione assorbe le eventuali differenze di peso sulle due corsie, assicurando un sostanziale parallelismo di queste alla base d'appoggio in qualsiasi condizione di sollevamento del ponte. The bridge according to the invention offers the advantage of eliminating any direct connection between the two lanes, and therefore of not creating any obstacle to the workers working under the raised vehicle or to a possible mobile transverse trolley for the entire length of the lanes. Furthermore, the torsion bar absorbs any weight differences on the two lanes, ensuring a substantial parallelism of these to the support base in any bridge lifting condition.

Vantaggiosamente il ponte sollevatore può essere provvisto di una coppia di martinetti oleodinamici a semplice effetto disposti tra ciascuna corsìa ed il corrispondente montante. Nel caso di una sola coppia di montanti collegati da una barra di torsione è preferibile che i martinetti oleodinamici siano disposti tra ciascuna corsia ed il corrispondente montante non interessato dalla barra di torsione. Advantageously, the lifting bridge can be provided with a pair of single-acting hydraulic jacks arranged between each lane and the corresponding upright. In the case of a single pair of uprights connected by a torsion bar, it is preferable that the hydraulic jacks are arranged between each lane and the corresponding upright not affected by the torsion bar.

Vantaggiosamente il ponte sollevatore può essere provvisto di piani inclinati di raccordo tra le corsie abbassate ed il pavimento, detti piani inclinati essendo provvisti di cinematismi atti a provocare il loro ripiegamento automatico mano a mano che le corsie si sollevano. Advantageously, the lifting bridge can be provided with inclined planes of connection between the lowered aisles and the floor, said inclined planes being provided with kinematic mechanisms capable of causing their automatic folding as the aisles are raised.

Allo scopo di offrire adeguate garanzie di sicurezza il ponte può essere vantaggiosamente provvisto, all'ingresso di ciascun martinetto, di una valvola di blocco agente nel senso di impedire la fuoriuscita del fluido operativo dal relativo In order to offer adequate safety guarantees, the bridge can advantageously be provided, at the inlet of each jack, with a blocking valve acting in the sense of preventing the operating fluid from escaping from the relative

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martinetto quando la differenza di pressione tra l'interno e l'esterno del martinetto stesso supera un prefissato valore. jack when the pressure difference between the inside and the outside of the jack itself exceeds a predetermined value.

Sempre allo scopo di offrire adeguate agaranzie di sicurezza il ponte può essere provvisto, in corrispondenza di ciascun martinetto di sollevamento, di un arpionismo di arresto comprendente una slitta dentata mobile ed un nottolino con essa cooperante, la dentatura della slitta essendo tale da consentire il sollevamento del ponte e da contrastarne l'abbassamento. Again in order to offer adequate safety guarantees, the bridge can be provided with a stop ratchet at each lifting jack comprising a movable toothed slide and a pawl cooperating with it, the toothing of the slide being such as to allow lifting of the bridge and to contrast its lowering.

Vantaggiosamente la slitta mobile può essere costituita da un organo articolato alla corrispondente corsia in prossimità del martinetto di sollevamento e provvisto di una porzione dentata e di una massa agente per gravità nel senso di mantenere la porzione dentata impegnata con il bordo di detto martinetto, mezzo essendo previsto per disimpegnare detta porzione dentata dal bordo del martinetto di sollevamento. Advantageously, the mobile slide can be constituted by an element articulated to the corresponding lane near the lifting jack and provided with a toothed portion and a mass acting by gravity in the sense of keeping the toothed portion engaged with the edge of said jack, the means being provided for disengaging said toothed portion from the edge of the lifting jack.

La presente invenzione viene qui di seguito ulteriormente chiarita con riferimento alle allegate tavole di disegni, in cui: The present invention is further clarified below with reference to the attached drawings, in which:

la fig. 1 mostra in vista laterale il ponte di sollevamento secondo l'invenzione, fig. 1 shows a side view of the lifting bridge according to the invention,

la fig. 2 lo mostra in pianta, fig. 2 shows it in plan,

la fig. 3 lo mostra secondo la sezione III-III di fig. 2, la fig. 4 mostra in vista laterale il particolare ingrandito di un piano inclinato di raccordo in configurazione distesa (ponte abbassato), fig. 3 shows it according to section III-III of fig. 2, fig. 4 shows a side view of the enlarged detail of an inclined connection plane in an extended configuration (lowered bridge),

la fig. 5 mostra lo stesso particolare in configurazione intermedia (ponte parzialmente sollevato), fig. 5 shows the same detail in an intermediate configuration (partially raised bridge),

la fig. 6 lo mostra in configurazione ripiegata (ponte completamente sollevato) e la fig. 7 mostra in vista laterale il particolare ingrandito di un martinetto di sollevamento e dell'arpionismo di ritegno ad esso associato. fig. 6 shows it in a folded configuration (bridge completely raised) and fig. 7 shows a side view of the enlarged detail of a lifting jack and the associated harpoon mechanism.

Come si vede dalle figure il ponte sollevatore secondo l'invenzione comprende una coppia di longheroni di base 1,1', recanti incernierati ciascuno due montanti 2, 2' e 3, 3', a loro volta incernierati all'estremità superiore a due corsie 4, 4'. As can be seen from the figures, the lift bridge according to the invention comprises a pair of base rails 1,1 ', each with two hinged uprights 2, 2' and 3, 3 ', in turn hinged at the upper end with two lanes 4, 4 '.

La distanza tra i punti di articolazione dei montanti 2, 3 e 2', 3' ai longheroni di base lei' rispettivamente è eguale alla distanza tra i due punti di articolazione dei montanti stessi alle corsie 4 e 4', sicché ciascun complesso formato da una coppia di montanti 2, 3 e 2', 3', dal relativo longherone di base 1 e 1' e dalla sovrastante corsia 4 e 4' costituisce un parallelogramma articolato. The distance between the pivot points of the uprights 2, 3 and 2 ', 3' to the base longitudinal members she 'respectively is equal to the distance between the two pivot points of the uprights themselves to lanes 4 and 4', so that each complex formed by a pair of uprights 2, 3 and 2 ', 3', from the relative base longitudinal member 1 and 1 'and from the overhanging lane 4 and 4' constitutes an articulated parallelogram.

I due montanti posteriori 3, 3' sono tra loro inferiormente collegati attraverso una robusta barra di torsione 5, opportunamente coperta, per ragioni di sicurezza, da una pedana 6. The two rear uprights 3, 3 'are mutually connected below by means of a sturdy torsion bar 5, suitably covered, for safety reasons, by a platform 6.

Ciascuna corsia 4,4' è provvista all'estremità anteriore di un ostacolo amovibile 7 per il veicolo, ed all'estremità posteriore di un piano inclinato, indicato genericamente con 8, per il raccordo con il pavimento, quando le corsie 4 e 4' sono abbassate. Each lane 4,4 'is provided at the front end with a removable obstacle 7 for the vehicle, and at the rear end with an inclined plane, generally indicated by 8, for the connection with the floor, when lanes 4 and 4' are lowered.

Ciascun piano inclinato 8 è costituito da due porzioni 9 e 10, tra loro articolate e provviste di un complesso di ci-nematismi azionati da un'asta 11 collegata al relativo montante posteriore 3, 3'. Each inclined plane 8 consists of two portions 9 and 10, articulated together and provided with a set of mechanisms activated by a rod 11 connected to the relative rear upright 3, 3 '.

L'articolazione tra ciascuna corsia 4, 4' e la porzione 9 del relativo piano inclinato 8 avviene attorno ad un asse 12 non passante per l'estremità della porzione 9 stessa, di guisa che quando detta porzione si dispone verticale, o comunque inclinata (ponte completamente sollevato o parzialmente sollevato) un suo tratto estremale 13 emerge dal piano superiore della relativa corsia 4,4' e costituisce l'arresto posteriore per il veicolo. The articulation between each lane 4, 4 'and the portion 9 of the relative inclined plane 8 takes place around an axis 12 which does not pass through the end of the portion 9 itself, so that when said portion is arranged vertically, or in any case inclined ( bridge completely raised or partially raised) an end portion 13 emerges from the upper plane of the relative lane 4,4 'and constitutes the rear stop for the vehicle.

Tra ciascun montante anteriore 3, 3' e la relativa corsia 4, 4' è interposto un martinetto oleodinamico 14 a semplice effetto per il sollevamento del ponte. Più precisamente il cilindro del martinetto 14 è articolato ad orecchiette 15 saldate ai montanti posteriori 2, 2', mentre l'estremità della relativa asta 16 è articolata ad orecchiette 17 saldate alle corsie 4, 4'. La camera di ciascun cilindro 14 comunica con il circuito idraulico esterno 18 attraverso una valvola di blocco 19, cioè attraverso una valvola, di per sé nota, la quale impedisce la fuoriuscita del fluido operativo dal cilindro 14 quando la differenza tra la pressione esterna e la pressione interna supera un prefissato valore. A single-acting hydraulic jack 14 is interposed between each front upright 3, 3 'and the relative lane 4, 4' for lifting the bridge. More precisely, the cylinder of the jack 14 is articulated with ears 15 welded to the rear uprights 2, 2 ', while the end of the relative rod 16 is articulated with ears 17 welded to the lanes 4, 4'. The chamber of each cylinder 14 communicates with the external hydraulic circuit 18 through a block valve 19, i.e. through a valve, known per se, which prevents the operating fluid from escaping from the cylinder 14 when the difference between the external pressure and the internal pressure exceeds a predetermined value.

Alle orecchiette 17 di ciascuna corsia 4, 4' è inoltre articolato un organo 20 comprendente una massa 21 ed una porzione dentata 22; la dentatura di detta porzione 22 è rivolta verso l'alto e può impegnarsi nella ghiera posteriore 23 del corrispondente cilindro 14 costituente il nottolino di un arpionismo di ritegno. An element 20 comprising a mass 21 and a toothed portion 22 is also articulated to the ears 17 of each lane 4, 4 '; the toothing of said portion 22 faces upwards and can engage in the rear ring nut 23 of the corresponding cylinder 14 constituting the pawl of a retaining harpoon.

In assenza di sollecitazioni esterne la posizione di ciascun organo 20, imposta dal peso della massa 21, è tale da mantenere la porzione dentata 22 impegnata con la ghiera 23; tale posizione può essere variata per rotazione dell'organo 20 attorno al suo perno 24 di articolazione alle orecchiette 17, grazie all'intervento di un piccolo martinetto oleopneumatico 25 solidale alla corsia 4, 4' provvisto di una molla (non rappresentata) per il ritorno elastico in condizioni di riposo. In the absence of external stresses, the position of each member 20, imposed by the weight of the mass 21, is such as to keep the toothed portion 22 engaged with the ring nut 23; this position can be varied by rotation of the member 20 around its pivot 24 for articulation to the ears 17, thanks to the intervention of a small oil-pneumatic jack 25 integral with lane 4, 4 'provided with a spring (not shown) for the return elastic in resting conditions.

Il funzionamento del ponte secondo l'invenzione è il seguente: The operation of the bridge according to the invention is as follows:

nella configurazione abbassata i martinetti 14 si trovano in condizione di minima elongazione e sono completamente alloggiati al di sotto delle corsie 4,4', le quali appoggiano sui rispettivi longheroni 1 e 1'; i piani inclinati 8 si presentano nella configurazione distesa (cfr. fig. 4) e costituiscono il raccordo tra il pavimento e le corsie 4, 4'; la porzione dentata 22 degli organi 20 si trova al di sotto del corrispondente martinetto 14. in the lowered configuration the jacks 14 are in a minimum elongation condition and are completely housed under the aisles 4,4 ', which rest on the respective longitudinal members 1 and 1'; the inclined planes 8 are presented in the extended configuration (see fig. 4) and constitute the connection between the floor and the aisles 4, 4 '; the toothed portion 22 of the members 20 is located below the corresponding jack 14.

Per sollevare il ponte si immette il fluido entro il cilindro dei martinetti 14 attraverso le valvole di blocco 19. L'elongazione dei martinetti 14, cioè la fuoriuscita del relativa stelo 16 provoca un aumento graduale dell'angolo compreso tra i montanti anteriori 2, 2' ed il tratto posteriore della corrispondente corsia 4, 4', ed il conseguente sollevamento di questa. Mano a mano che le corsie 4, 4' si sollevano, i montanti 3,3', che ovviamente si mantengono paralleli ai montanti 2, 2', provocano una trazione assiale delle aste 11 nel senso della freccia 26 nelle figg. 4 e 5 e, grazie al sistema di leve che collegano le due porzioni 9 e 10 dei piani inclinati 8, il ripiegamento di detti piani inclinati (cfr. figg. 5 e 6). In questa fase la porzione 13 sporge dal piano superiore della relativa corsia 4,4' e costituisce l'ostacolo posteriore per il veicolo nel frattempo salito sul ponte. To raise the bridge, the fluid is introduced into the cylinder of the jacks 14 through the block valves 19. The elongation of the jacks 14, i.e. the release of the relative stem 16, causes a gradual increase in the angle between the front uprights 2, 2 'and the rear section of the corresponding lane 4, 4', and the consequent lifting of this. As the lanes 4, 4 'rise, the uprights 3,3', which obviously remain parallel to the uprights 2, 2 ', cause axial traction of the rods 11 in the direction of the arrow 26 in figs. 4 and 5 and, thanks to the system of levers that connect the two portions 9 and 10 of the inclined planes 8, the folding of said inclined planes (see figs. 5 and 6). In this phase the portion 13 protrudes from the upper floor of the relative lane 4,4 'and constitutes the rear obstacle for the vehicle that has meanwhile climbed onto the bridge.

Sempre durante il sollevamento del ponte la porzione dentata 22 dell'organo 20 scivola lungo la ghiera 23 del corrispondente martinetto 14 e costituisce in tal modo un arpionismo di ritegno che garantisce un'elevata sicurezza anche nel caso di guasto all'impianto idraulico di sollevamento. Again during the lifting of the bridge, the toothed portion 22 of the member 20 slides along the ring nut 23 of the corresponding jack 14 and thus constitutes a retaining ratchet which guarantees high safety even in the event of failure of the hydraulic lifting system.

Quando il ponte è sollevato alla desiderata altezza, gli operai possono agevolmente operare in condizione di assoluta sicurezza e di elevata comodità, grazie all'assenza di qualsiasi traverso di collegamento tra le due corsie 4, 4'. Ciò, oltre a rendere agevoli le operazioni, consente l'impiego di un carrello 27, di tipo di per sé noto, mobile per tutta la lunghezza della corsia 4 e 4' ed eventualmente provvisto di un martinetto idraulico di sollevamento (non rappresentato). Le condizioni di lavoro risultano agevoli anche per il fatto che la barra di torsione 5 distribuisce uniformemente il When the bridge is raised to the desired height, the workers can easily operate in conditions of absolute safety and high comfort, thanks to the absence of any connecting beam between the two lanes 4, 4 '. This, in addition to facilitating the operations, allows the use of a trolley 27, of a type known per se, movable along the entire length of the lane 4 and 4 'and possibly equipped with a hydraulic lifting jack (not shown). The working conditions are also easy due to the fact that the torsion bar 5 evenly distributes the

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peso del veicolo sulle due corsie 4, 4', anche nel caso di differenze di carico, (che in pratica possono essere anche dell'ordine di oltre il 30%) ed assicurano un perfetto parallelismo di queste con il pavimento. weight of the vehicle on the two lanes 4, 4 ', even in the case of load differences (which in practice can also be in the order of over 30%) and ensure perfect parallelism of these with the floor.

Per abbassare il ponte vengono inizialmente alimentati i due martinetti 25, i quali, agendo sulle masse 21 degli organi 20, provocano il disimpegno della loro porzione dentata 22 dalla corrispondente ghiera 23 dei martinetti 14 e consentono che il fluido operativo venga spinto fuori dai martinetti stessi ad opera del peso del ponte e dell'automezzo da questo sostenuto. La corsa di discesa del ponte viene regolata da una valvola (non rappresentata) inserita nel circuito esterno di alimentazione. To lower the bridge, the two jacks 25 are initially fed, which, acting on the masses 21 of the members 20, cause the disengagement of their toothed portion 22 from the corresponding ring nut 23 of the jacks 14 and allow the operating fluid to be pushed out of the jacks themselves by the weight of the bridge and the vehicle supported by it. The downward stroke of the bridge is regulated by a valve (not shown) inserted in the external power supply circuit.

La valvola di blocco 19 che, come si è detto, impedisce la fuoriuscita del fluido operativo da ciascun martinetto 14 quando la differenza tra la pressione esterna e la pressione interna supera un prefissato valore, garantisce l'arresto della corsa di discesa nel caso in cui una perdita od un guasto al circuito idraulico potesse rendere troppo elevata tale velocità di discesa o, peggio ancora, potesse provocare la caduta del ponte. The shut-off valve 19 which, as has been said, prevents the escape of the operating fluid from each jack 14 when the difference between the external pressure and the internal pressure exceeds a predetermined value, guarantees the stopping of the descent stroke in the event that a leak or a fault in the hydraulic circuit could make this descent speed too high or, worse still, could cause the bridge to fall.

Naturalmente durante la discesa del ponte i piani inclinati 8 sono azionati in senso opposto e vengono riportati, al termine di tale corsa di discesa, nella configurazione distesa, illustrata in fig. 4. Of course, during the descent of the bridge, the inclined planes 8 are operated in the opposite direction and are returned, at the end of this descent stroke, to the extended configuration, shown in fig. 4.

5 Da quanto detto risulta chiaramente che il ponte sollevatore, oggetto della presente invenzione, offre, rispetto ai tradizionali ponti sollevatori a pantografo, numerosi vantaggi, tra i quali: 5 From what has been said it is clear that the lift bridge, object of the present invention, offers, compared to traditional scissor lift scales, numerous advantages, among which:

io — l'eliminazione di qualsiasi traverso di collegamento tra le due corsie 4, 4', e l'ottenimento di ima completa accessibilità a tutte le parti dell'automezzo; I - the elimination of any connecting beam between the two lanes 4, 4 ', and the obtaining of complete accessibility to all parts of the vehicle;

— la possibilità di applicare al ponte un carrello 27 mobile per tutta la lunghezza delle corsie 4,4'; - the possibility of applying a mobile trolley 27 along the length of the lanes 4,4 'to the bridge;

15 — una riduzione dell'ingombro longitudinale del ponte, pur con lunghi piani inclinati, grazie alla ripiegabilità degli stessi; 15 - a reduction in the longitudinal dimensions of the bridge, even with long inclined planes, thanks to the foldability of the same;

— un elevato grado di sicurezza anche durante l'abbassa- - a high degree of safety even when lowering

20 mento del ponte, quando cioè gli organi di sicurezza meccanica sono disinseriti. 20 of the bridge, ie when the mechanical safety devices are disengaged.

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3 fogli disegni 3 drawings sheets

Claims

636581 2 CLAIMS

1. Scissor lift bridge, particularly for motor vehicles, comprising a pair of lanes (4,4 '), each supported by a pair of uprights (2, 3, 2', 3 ') which are in turn articulated with two side members (1 , 1 ") resting on the floor, characterized in that the homologous uprights

(2, 2 'and / or 3, 3') of at least one pair are connected to each other via a torsion bar (5).

Lifting platform according to claim 1, characterized in that it is provided with a pair of single-acting hydraulic jacks (14) arranged between each lane (4, 4 ') and the corresponding upright (2,2', 3, 3 ').

Lifting bridge according to claim 2, wherein a single pair of uprights (3, 3 ') are connected by a torsion bar (5), characterized in that the hydraulic jacks (14) are arranged between each lane (4 , 4 ') and the corresponding upright (2, 2') not affected by the torsion bar (5).

Lifting platform according to claim 3, characterized in that the point of articulation of each hydraulic jack (14) to the relative lane (4,4 ') falls inside the points of articulation of the two uprights (2, 3, 2', 3 ') to the lane itself.

Lifting platform according to claim 1, characterized in that the torsion bar (5) is covered by a platform (6).

Lifting platform according to claim 1, characterized in that it is provided with inclined planes (8) for the connection between the lowered aisles (4,4 ') and the floor,

said inclined planes being provided with kinematic mechanisms capable of causing their automatic folding as the lanes (4, 4 ') rise.

Lifting platform according to claim 6, characterized in that each inclined plane (8) is articulated to the corresponding lane (4,4 ') and comprises two portions (9,10) mutually articulated together and connected by a system of levers operated by a rod (11) connected to an upright (3, 3 ') at a point other than the point of articulation of that upright to the lane (4,4').

8. Lifting bridge according to claim 1, characterized in that it is provided at the inlet of each jack (14) with a block valve (19) acting in the sense of preventing the operating fluid from leaking out of the jack (14) when the pressure difference between the inside and the outside of this exceeds a predetermined value.

9. Lifting bridge according to claim 8, characterized in that it is provided, in correspondence with each lifting jack (14), with a retaining harpoon comprising a mobile toothed slide (22) and a pawl (23) cooperating with it, the toothing of the slide being such as to allow the lifting of the bridge and to counteract its lowering.

Lifting platform according to claim 9, characterized in that the mobile slide is constituted by an element (20) articulated to the corresponding lane (4, 4 ') near the lifting jack (14) and provided with a toothed portion ( 22) and of a mass (21) acting by gravity in the sense of keeping the toothed portion (22) engaged with the edge (23) of said jack, means being provided for disengaging said toothed portion from the edge (23) of said jack lifting (14).

Lifting bridge according to claim 10, characterized in that it comprises a hydraulic jack (25) acting on the mass (21) to disengage the toothed portion (22) from the edge (23) of the lifting jack (14), called jack ( 25) being provided with a spring for the elastic return in the rest position.

The present invention relates to a scissor lift bridge, particularly for motor vehicles.

Lifting platforms used in car repair shops, body shops, etc. are known. They comprise two parallel side members or lanes, on which the vehicle is lifted, being said lanes that can be raised to allow convenient access to the lower part of the vehicle itself.

The lifting of the aisles can take place with different systems, mechanical, hydraulic, etc., and different models are now on the market. Among these, a type known as the "pantograph" type has found particular diffusion, in which each lane is articulated with two uprights in turn articulated to a longitudinal member resting on the floor and forming an articulated parallelogram altogether.

The advantages of this solution consist in a limited size of the bridge in the lowered condition, and in the ease of carrying out the movement of the articulated parallelogram with hydraulic systems.

In order to prevent the two aisles from rising differently, it is known to connect them with sturdy cross beams, practically forming a platform with these which lifts resting on the four uprights (two on each side).

A drawback of these known scissor lift bridges consists in the fact that the cross beams, during the practical use of the bridge, hinder the movements of the workers and partially shield the vehicle preventing, or in any case making access to the shielded parts difficult.

Another drawback consists in the fact that if a transverse trolley is required along the aisles and equipped with a jack for the further lifting of the vehicle or parts thereof with respect to the aisles, the crosspieces are an obstacle to the movement of the trolley and therefore impose complex, expensive and not easy to manufacture and use solutions.

According to the invention, the problem is solved with a scissor lift, particularly for motor vehicles, comprising a pair of lanes each supported by a pair of uprights which are in turn articulated with two side members resting on the floor, characterized in that the homologous uprights of at least one pair are connected to each other via a torsion bar.

The bridge according to the invention offers the advantage of eliminating any direct connection between the two lanes, and therefore of not creating any obstacle to the workers working under the raised vehicle or to a possible mobile transverse trolley for the entire length of the lanes. Furthermore, the torsion bar absorbs any weight differences on the two lanes, ensuring a substantial parallelism of these to the support base in any bridge lifting condition.

Advantageously, the lifting bridge can be provided with a pair of single-acting hydraulic jacks arranged between each lane and the corresponding upright. In the case of a single pair of uprights connected by a torsion bar, it is preferable that the hydraulic jacks are arranged between each lane and the corresponding upright not affected by the torsion bar.

Advantageously, the lifting bridge can be provided with inclined planes of connection between the lowered aisles and the floor, said inclined planes being equipped with kinematic mechanisms capable of causing their automatic folding as the aisles are raised.

In order to offer adequate guarantees of safety, the bridge can advantageously be provided, at the inlet of each jack, with a blocking valve acting in the sense of preventing the escape of the operating fluid from the relative

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jack when the pressure difference between the inside and the outside of the jack itself exceeds a predetermined value.

Again in order to offer adequate safety guarantees, the bridge can be equipped with a stop ratchet at each lifting jack, comprising a movable toothed slide and a pawl cooperating with it, the toothing of the slide being such as to allow lifting of the bridge and to prevent its lowering.

Advantageously, the mobile slide can be constituted by an element articulated to the corresponding lane near the lifting jack and provided with a toothed portion and a mass acting by gravity in the sense of keeping the toothed portion engaged with the edge of said jack, the means being provided for disengaging said toothed portion from the edge of the lifting jack.

The present invention is further clarified below with reference to the attached drawings, in which:

fig. 1 shows a side view of the lifting bridge according to the invention,

fig. 2 shows it in plan,

fig. 3 shows it according to section III-III of fig. 2, fig. 4 shows a side view of the enlarged detail of an inclined connection plane in an extended configuration (lowered bridge),

fig. 5 shows the same detail in an intermediate configuration (partially raised bridge),

fig. 6 shows it in a folded configuration (bridge completely raised) and fig. 7 shows a side view of the enlarged detail of a lifting jack and the associated harpoon mechanism.

As can be seen from the figures, the lift bridge according to the invention comprises a pair of base rails 1, 1 ', each with two hinged uprights 2, 2' and 3, 3 ', in turn hinged at the upper end with two lanes 4, 4 '.

The distance between the articulation points of the uprights 2, 3 and 2 ', 3' to the base longitudinal members 1 and 1 'respectively is equal to the distance between the two articulation points of the uprights themselves to lanes 4 and 4', so that each assembly formed by a pair of uprights 2, 3 and 2 ', 3', by the relative base longitudinal member 1 and 1 'and by the overhanging lane 4 and 4' constitutes an articulated parallelogram.

The two rear uprights 3, 3 'are mutually connected below by means of a sturdy torsion bar 5, suitably covered, for safety reasons, by a platform 6.

Each lane 4,4 'is provided at the front end with a removable obstacle 7 for the vehicle, and at the rear end with an inclined plane, generally indicated by 8, for the connection with the floor, when lanes 4 and 4' are lowered.

Each inclined plane 8 consists of two portions 9 and 10, articulated together and provided with a set of mechanisms activated by a rod 11 connected to the relative rear upright 3, 3 '.

The articulation between each lane 4, 4 'and the portion 9 of the relative inclined plane 8 takes place around an axis 12 which does not pass through the end of the portion 9 itself, so that when said portion is arranged vertically, or in any case inclined ( bridge completely raised or partially raised) an end portion 13 emerges from the upper plane of the relative lane 4, 4 'and constitutes the rear stop for the vehicle.

A single-acting hydraulic jack 14 is interposed between each front upright 3, 3 'and the relative lane 4, 4' for lifting the bridge. More precisely, the cylinder of the jack 14 is articulated with orecchiette 15 5 welded to the rear uprights 2, 2 ', while the end of the relative rod 16 is articulated with orecchiette 17 welded to the lanes 4,4'. The chamber of each cylinder 14 communicates with the external hydraulic circuit 18 through a block valve 19, i.e. through a valve, per se known, which prevents the operating fluid from escaping from the cylinder 14 when the difference between the external pressure and the internal pressure exceeds a predetermined value.

An element 20 comprising a mass 21 and a toothed portion 22 is also articulated to the ears 17 of each lane 4, 4 '; the toothing of said portion 22 faces upwards and can engage in the rear ring nut 23 of the corresponding cylinder 14 constituting the pawl of a retaining harpoon.

In the absence of external stresses, the position of each member 20, imposed by the weight of the mass 21, is such as to keep the toothed portion 22 engaged with the ring nut 23; this position can be varied by rotation of the member 20 around its pivot 24 for articulation to the ears 17, thanks to the intervention of a small pneumatic hydraulic jack 25 integral with the lane 4,4 'provided with a spring (not shown) for the elastic return in rest conditions.

The operation of the bridge according to the invention is as follows:

30 in the lowered configuration the jacks 14 are in a minimum elongation condition and are completely housed under the aisles 4, 4 ', which rest on the respective longitudinal members 1 and 1'; the inclined planes 8 are presented in the extended configuration (see fig. 4) and constitute the 35 connection between the floor and the aisles 4, 4 '; the toothed portion 22 of the members 20 is located below the corresponding jack 14.

To raise the bridge, the fluid is introduced into the cylinder of the jacks 14 through the block valves 19. 40 The elongation of the jacks 14, i.e. the release of the relative stem 16, causes a gradual increase in the angle between the front uprights 2, 2 'and the rear section of the corresponding lane 4, 4', and the consequent lifting of this. As the lanes 4, 4 'rise, 45 the uprights 3, 3', which obviously remain parallel to the uprights 2, 2 ', cause axial traction of the rods 11 in the direction of the arrow 26 in figs. 4 and 5 and, thanks to the system of levers that connect the two portions 9 and 10 of the inclined planes 8, the folding of said inclined planes (see figs. 5 and so 6). In this phase the portion 13 protrudes from the upper plane of the relative lane 4, 4 'and constitutes the rear obstacle for the vehicle that has meanwhile climbed onto the bridge.

Again during the lifting of the bridge, the toothed portion 22 of the member 20 slides along the ring nut 23 of the corresponding jack 14 and thus constitutes a retaining ratchet which guarantees high safety even in the event of failure of the hydraulic lifting system .

When the bridge is raised to the desired height, the 50 workers can easily operate in conditions of absolute safety and high comfort, thanks to the absence of any connecting beam between the two lanes 4, 4 '. This, in addition to making operations easier, allows the use of a trolley 27, of a type known per se, movable along the entire length of the lane 4 and 4 'and possibly equipped with a hydraulic lifting jack (not shown) . The working conditions are also easy due to the fact that the torsion bar 5 evenly distributes the

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weight of the vehicle on the two lanes 4, 4 ', even in the case of load differences (which in practice can also be in the order of over 30%) and ensure perfect parallelism of these with the floor.

To lower the bridge, the two jacks 25 are initially fed, which, acting on the masses 21 of the members 20, cause the disengagement of their toothed portion 22 from the corresponding ring nut 23 of the jacks 14 and allow the operating fluid to be pushed out of the jacks themselves by the weight of! bridge and the vehicle supported by it. The downward stroke of the bridge is regulated by a valve (not shown) inserted in the external power supply circuit.

The shut-off valve 19 which, as has been said, prevents the escape of the operating fluid from each jack 14 when the difference between the external pressure and the internal pressure exceeds a predetermined value, guarantees the stopping of the descent stroke in the event that a leak or a fault in the hydraulic circuit could make this descent speed too high or, worse still, could cause the bridge to fall.

Of course, during the descent of the bridge, the inclined planes 8 are operated in the opposite direction and are returned, at the end of this descent stroke, to the extended configuration, shown in fig. 4.

5 From what has been said it is clear that the lift bridge, object of the present invention, offers, compared to traditional scissor lift scales, numerous advantages, among which:

I - the elimination of any connecting beam between the two lanes 4,4 ', and obtaining complete accessibility to all parts of the vehicle;

- the possibility of applying a mobile trolley 27 along the length of the lanes 4,4 'to the bridge;

15 - a reduction in the longitudinal dimensions of the bridge, even with long inclined planes, thanks to the foldability of the same;

- a high degree of safety even when lowering

2nd chin of the bridge, ie when the mechanical safety devices are disengaged.

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3 drawings sheets