PROTECTIVE CASING FOR CONTROL LEVERS

Abstract: The invention relates to a protective casing for control levers (6) which on one hand have to be exposed and on the other hand to be protected in an enclosed condition. The levers (6) are arranged on a common carrier (8). The protective casing comprises two shell-shaped parts (12, 13) which are articulatedly connected with a carrier (8) via joints (20, 20') and interconnected via gear segments (23) or other means which forcedly provide a pivoting of the shell parts (12, 13) in opposite directions around the appurtenant joints (20, 20').

Description: PROTECTIVE CASING FOR CONTROL LEVERS Tpchnical Field of the Invention This invention relates to a protective casing for control levers which on one hand have to be exposed and on the other hand to be protected in an enclosed condition, the indi¬ vidual lever being arranged on a carrier. Background of the Invention and Prior Art The origin of the present invention is to be found in the field of control units for cranes. Vehicle-borne piece good cranes usually comprise two control units which are placed on either side of the vehicle and either of which comprises a set of control levers, by means of which the different functions of the crane can be controlled, e.g., the turning of a crane post, the raising and lowering, respectively, of one or several lif¬ ting jibs, the turning of a rotator, the winding-in of a winch hook, and similar. More specifically, the levers cooperate in pairs in the two units so that each coupled pair of levers actuates a common operating means, e.g. a hydraulic valve, which in turn determines the desired crane function. Due to space reasons, the levers are most suitably arranged in a horizontal row on appurtenant carriers, normally in a number of four to eight. In practice, it is preferred to interconnect the pairs of levers in the two control units via crosslaid bars which guaran¬ tee a mutually similar placing of the levers in the two lever sets. See in this context SE 8201833-4. However, a disadvantage of previously known control units of this type is that the levers are always exposed and unprotected. This involves that snow and ice may freely deposit in the area of the levers and make the necessary manual actua¬ tion of these difficult. By the fact that the long and narrow levers protrude freely from the carriers behind, they may also easily be subjected to unintentional actuation, e.g. by the operator accidentally falling or leaning against the lever set. A minor, although in practice irritating inconvenience, is that the levers in their exposed state are easily made dirty, whereby the physical contact of the operator with the levers via the fingers becomes unpleasant. Ob-ierts and Features of the Invention The present invention aims at eliminating the above mentioned disadvantages and providing a well adapted protective casing for control levers of the described type. Thus, a prima object of the invention is to provide a protective casing whic on one hand in a shut state efficiently excludes snow, ice and dirt from any contact with the levers, and on the other hand makes the access to the levers possible in a simple and smooth manner. A further object of the invention is to provide a pro¬ tective casing which may be opened without having to be removed from the appurtenant carrier or intrude upon the available spac for other components in the proximity of the casing, for instance parts or attachments for a crane unit. A special objec of the invention is to provide a protective casing that does no merely protect the levers in its closed or shutting state but also serves as a protection against unintentional manual actua- tion of the levers when it has been opened during the exposure of the levers. Still another object of the invention is to provide a protective casing that may be opened and closed in a simple and quick manner. Thus, the operator shall not have to resort to complicated and time-consuming measures for opening and closing the casing, respectively. According to the invention, at least the primary objec is attained by the features as defined in the characterizing clause of claim 1. Furthermore, preferred embodiments of the invention are defined in the dependent claims . Brie-F Description of the Appended Drawings In the drawings: fig 1 is a perspective view of a crane construction with two control units in which are comprised protective casing according to the present invention, fig 2 is a perspective view showing one of the control units on an enlarged scale, with the protective casing open, fig 3 is a side view showing the same protective casing in an open state, fig 4 is a corresponding side view showing the casing in a closed state, fig 5 is an enlarged, transparent side view of the casing, and fig 6 is an equally transparent side view showing the protec¬ tive casing to a fixed control unit included in a crane unit according to fig 1. Detailed Description of Preferred Embodiments of the Invention In fig 1 a crane unit is shown which, besides a crane post or body 1 and turnable beams 2, comprises a foot or base part designated by reference numeral 3 in its entirety, which in practice is mounted behind and near a cabin on the chassis of a vehicle (not shown) . At opposed ends of the foot part 3 are the control units, generally designated 4, 5, of which the former in the example is movably arranged, while unit 5 is fixedly mounted on the foot part. In each control unit is included a set of levers designated 6. In the area behind each control unit 4, 5 support legs 7 are arranged. In the shown example, the crane unit is intended to be mounted on a left-hand drive vehicle, implying that the movable control unit 4 is located on the driver's side of the vehicle, while the fixed control unit is located on the opposite longitudinal side of the vehicle. Reference is now made to fig 2 to 5 which illustrate in more detail the movable control unit 4. In this case, the levers 6 are mounted on a carrier designated 8, which is pivotable via joints 9 relative to an installation part 10 being fixedly connected with the body 3, and thereby foldable between a folded-out (e.g. horizontal) position as shown in fig 2, and a (not shown) vertical, folded-up position. In practice, the carrier 8 may have the character of a box at the free gable end of which the levers 6 are mounted in a common plane which in the folded-out state according to fig 2 is substantially horizontal. In the example, the number of levers is six. In practice, speci¬ fically the shown levers, which are intended for controlling a crane, are pivotable upwards as well as downwards from a middl neutral position. The levers may consist of long and narrow ro or tubes with a length within the range of 10 to 20 cm. As initially mentioned, the levers in the unit 4 may be connected with the levers in the unit 5 via a set (not shown) of crossla bars built-in in the body 3, which bars guarantee that for instance the left lever in unit 4 is the equivalent of the leftmost lever in unit 5, which lever actuates one and the sam operating means (e.g., a plunger of a hydraulic valve) carryin out a given crane function. Thus, for an operator who is facin either of the units 4, 5, the levers 6 obtain one and the same interrelated placing. According to the invention, a casing designated by reference numeral 11 in its entirety is provided in order to protect the levers 6, which casing comprises two shell-shaped parts 12, 13 of which the former is located underneath the levers 6 and the latter above the same. The first, lower shell part 12 comprises a main wall 14, two side walls 15, 15' and a gable wall 16 interconnecting said walls. In a corresponding way, the upper shell part 13 comprises a main wall 17, two sid walls 18, 18' and a gable wall or gable edge 19. As may be clearly seen in fig 2 to 5, the gable wall 16 of the lower she part 12 has a height that is many times larger than the corres¬ ponding gable wall 19 on the upper shell part. This implies th the side walls 15, 15' on the lower shell part taper in the direction away from the gable wall 16, while the corresponding side walls 18, 18' on the upper shell part taper in the direc¬ tion of the gable wall 19. The lower shell part 12 is connecte with the carrier 8 via a joint construction 20 which in practi may consist of either a through shaft or two separate joint taps. However, in both cases the joint 20 is located at a point which is situated near the main wall 14 as well as the inner e of the respective side wall 15, 15' . More specifically, the si walls 15, 15' are provided with a laterally dislocated end portion 21, which is located within a free end of one of two side flanges 22 comprised by the box-shaped carrier 8. The joi 20 in question intersects both the box side flange 22 and said wall portion 21, the individual side wall 15, 15' otherwise being mainly located in the same plane as the box side flange 22. In an analogous way, the side walls 18, 18' of the upper shell part 13 are connected with the carrier via a joint construction 20' . In the region of their inner ends, the pairs of side walls 15, 15' and 18, 18' , respectively, are made with about the same heights. From this region, the side walls 18, 18' converge in the direction of the free gable wall or edge 19, while the walls 15, 15' diverge in the direction of the corresponding gable wall 16. In practice, this involves that the lower shell part 12 - on condition of an approximately uniform material thickness - contains a larger mass of material than the upper shell part 13. In other words, the lower shell part 12 is heavier than the upper one . As may be clearly seen in fig 5 (see also fig 2) , arched gear rims or gear rim segments 23, 23' are provided on the edges facing each other of the internal end portions 21 of the respective pair of side walls 15, 18; 15' , 18', which rims or segments are in engagement with each other. More specifi¬ cally, each gear segment is arc-shaped and located concentri¬ cally in relation with the appurtenant joint 20 and 20' , respec¬ tively. By the fact that the cogs in the gear segments are in constant engagement with each other, one of the shell parts will forcedly be pivoted around the appurtenant joint as soon as the other shell part is pivoted in relation to its joint. More specifically, both shell parts will forcedly be pivoted in opposite directions around the appurtenant joints, so that the lower shell part 12 is pivoted in a downward direction around the joint 20, at the same time as the upper shell part 13 is pivoted in an upward direction around the joint 20' . Between the two shell parts 12, 13 acts a locking means 24 with the purpose of holding the shell parts together in the closed state of the casing. As shown in the drawings, the locking means 24 may advantageously be placed on one of the two side walls 15 , 15 ' of the lower shell part 12 and have an internal, movable part (not shown) that cooperates with a fixe stop on the inside of the corresponding side wall 18, 18' at t upper shell part 13. On the underside of the main wall 14 of t lower shell part 12 is arranged a handle with the shape of an section 25, by means of which the carrier 8 may be folded when the two shell parts 12, 13 of the protective casing are locked together by the locking means 24. According to the example, on the underside of the mai wall 17 of the upper shell part 13 is arranged an indicator panel 26 immediately adjacent to the free end of the shell par In this panel may be included function symbols that are lighte up when a given crane function is activated by means of any of the levers 6. The described protective casing works in the followin way. In the shutting or closed state that is illustrated in fi 4, the shell parts 12, 13 are reliably held together by means the locking means 24. In this state, the levers 6 are protecte against the intrusion of particles as well as mechanical damag When the operator wishes to use the crane, the locking functio of the locking means 24 is eliminated, whereby the shell parts 12, 13 become free to pivot around the appurtenant joints 20, 20 ' . On one hand by the fact that the lower shell part is heavier than the upper one, and on the other hand by the fact that the two shell parts are connected with each other over th gear segments 23, 23' , the lower shell part will, at its pivo¬ ting in a downward direction or clockwise around the appurtena joint 20, carry the upper shell part and force the same to mov upwards in a counter-clockwise direction around the appurtenan joint 20' . In practice, this means that the two shell parts automatically open like a jaw as soon as the locking means 24 liberated. Hereby, the levers 6 are exposed and become easily accessible for the user. With special reference to fig 3, it should be noted that the main wall 14 of the lower shell part, in the maximall folded-out or lowered end position of the shell part, extends about 45° to the horizontal plane, as does the main wall 17 of the upper shell part. In this state, the upper edge 16' of the gable wall 16 of the lower shell part 12 forms the portion of the shell part that is horizontally most distal from the carrier. More specifically, the edge portion 16' is located in a vertical plane that is more distanced from the carrier 8 than the free ends of the levers 6, implying that the free end of the lower shell part will serve as a shock protector that counter¬ acts unintentional manual actuation of the levers, for instance as a consequence of the user accidentally falling or leaning against the lever set. That the edge portion 16', as described, is located outside the levers, is due to the fact that it is situated considerably higher up than an imaginary horizontal central plane through the carrier, in its initial position before opening. Therefore, in spite of the fact that also the edge portion 16' moves about 45° when folding out, it will be located comparatively near below the lever set, in the end position. In this context it should be noted that the correspon¬ ding free end or gable edge 19 of the upper shell part 13 is located in a vertical plane greatly within the free ends of the levers; involving that the upper shell part in this position does not obstruct the access to the levers. When the casing is to be closed, one of the shell parts, suitably the lower one 12, is moved by hand from its folded-out end position towards the levers, the other shell part automatically being carried with it thanks to the engagement of the gear segments with each other. When the shell parts have been returned to their initial positions they are locked, suitably automatically, by means of the locking means 24. The protective casing of the fixed control unit 5, which is shown on an enlarged scale in fig 6, is basically built up in the same way as the protective casing according to fig 2 to 5. However, it should be noted that the control units 6 of the unit 5 are in an entirely horizontal position in their neutral state, while the levers 6 in the unit 4 are slightly inclined in a downward direction, when in the corresponding state. Furthermore, in the fixed unit 5 the carrier has the shape of a bracket 8' in lieu of a box. Feasible Modifications of the Invention It is evident that the invention is not restricted solely to the embodiments as described and shown in the dra¬ wings. Thus, it is feasible to apply the invention also for s lever-equipped arrangements that are not related to control units for cranes. Nor do the two shell parts which together f a protective casing, have to be horizontally arranged, with t one shell part over the other one. Thus, the placing in space the casing is not critical. It is also feasible to form and utilize a protective casing for only one lever, in place of several levers according to the given examples. Of course, al the geometrical shape of the respective shell parts may vary quite considerably within the framework of the appended claims Moreover, it is possible to use other means in place of speci- fically gear segments, e.g. lever or linkage mechanisms in or to bring about the forced, simultaneous pivoting of the shell parts in opposite directions. Furthermore, in the protective casings special means may be provided in order to avoid that t control levers shake or vibrate during transport. It is for instance possible to insert internal cushions of foam-rubber o any other soft material into at least the two shell parts of t movable protective casing, which material bears on the levers when the protective casing is closed. It is also feasible to interconnect the locking means 24 in question to the two protective casings 4, 5 via means which make the opening of either casing impossible as soon as the other one has been opened.

Claims: Claims 1. A protective casing for control levers which on one hand have to be exposed and on the other hand to be protected in an enclosed condition, the individual lever (6) being arranged on a carrier (8), c h a r a c t e r i z e d in that it comprises two shell-shaped parts (12, 13) , which are articulatedly connec¬ ted with the carrier (8) and interconnected via means (23, 23') which forcedly provide simultaneous pivoting of the shell parts (12, 13) in opposite directions around the appurtenant joints (20, 20' ) . 2. Protective casing according to claim 1, a plurality of levers (6) being arranged side by side in a substantially horizontal row on the carrier (8) , c h a r a c t e r i z e d in that a first shell part (12) is placed underneath the row of levers and arranged to be pivoted in a downward direction away from the levers when the protective casing is to be opened, while the second shell part (13) is placed above the row of levers and arranged to be pivoted upwards at the opening. 3. Protective casing according to claim l or 2, c h a r a c ¬ e r i z e d in that between the shell parts (12, 13) acts a locking means (24) with the purpose of holding said shell parts together in the closed or lever-enclosing state of the casing. 4. Protective casing according to claim 2 and 3, c h a r a c ¬ t e r i z e d in that the first, lower shell part (12) is heavier than the second shell part (13) in order to provide an automatic pivoting of the shell parts from the closed state towards the open state, when liberating the locking means (24) . 5. Protective casing according to any of claims 2 to 4, c h a r a c t e r i z e d in that the individual shell part (12, 13) has a main wall (14, 17), two side walls (15, 15'; 18, 18') and a gable wall (16, 19) at the free end of the main wall, said end being distal from the joints (20, 20'), and that the gable wall (16) of the lower shell part (12) has a height that is many times larger than the gable wall (19) of the upper she part (13) , the side walls (15, 15') of the lower shell part tapering in the direction away from the gable wall, towards th joint (20) , while the side walls (18, 18') of the upper shell part (20) taper in the direction away from the joint (20') , towards the gable wall (19) . 6. Protective casing according to claim 5, c h a r a c t e - r i z e d in that the individual shell part is connected with separate side flanges (22) on the carrier (8) via joints (20, 20') placed in the side walls (15, 15' ; 18, 18') of the shell parts, more specifically at points situated near both the main wall (14, 17) and an end of the appurtenant side wall. 7. Protective casing according to any of the preceding claims, c h a r a c t e r i z e d in that the means for the forcedly simultaneous pivoting of the shell parts (12, 13) consists of arched gear rims or gear rim segments (23, 23 ' ) . 8. Protective casing according to any of claims 2 to 7, c h a r a c t e r i z e d in that the two shell parts (12, 13 when pivoted into their mutually remote end positions, are inclined at an acute angle to a horizontal plane through the r of levers (6) , parts (16') of the lower shell part (12) protru ding somewhat farther from the carrier (8) than the levers (6) in order to serve as a shock protector with the purpose of counteracting any unintentional manual actuation of the levers

Inventors: SALAAKER ALLAN, SALAAKER, ALLAN
Applicants: HIAB AB, SALAAKER ALLAN, SALAAKER, ALLAN
Application year: 1995
Main classification: G05G5
IPC codes: B66C13, G05G5