CONVEYOR

Abstract: Conveyor comprising a stationary track (10), the extent of which comprises sections at different levels, movable elements (16) which are guided by the track for movement along this, a supporting member (34) on at least some of the movable members, and a device for maintaining the supporting member in a predetermined angular position regardless of the position of the movable element during its movement along the track, wherein the supporting member (34) is mounted for rotation about a substantially horizontal axis in the movable element (16), and wherein the device for maintaining the supporting member in the predetermined position comprises an actuating mechanism (37, 42) connected with the supporting member, and a guide path (40; 43) arranged wholly or partially along the stationary track to interact with the elements in the actuating mechanism. The conveyor is characterised in that the actuating mechanism (37, 42) connected to the supporting member (34) is arranged on one hand to lock the supporting member in the predetermined angular position when the movable member (16) is moving linearly along the track, and on the other hand to infinitely-variably adjust the supporting member so as to maintain its predetermined angular position when the movable member is moving along the track and being subjected to a vertical change in direction.

Description: CONVEYOR The present invention relates to a conveyor compris¬ ing a stationary track the extent of which comprises sections at different levels, movable elements which are guided by the track for movement along this, a supporting member on at least some of the movable ele¬ ments, and a device for maintaining the supporting mem¬ ber in a predetermined angular position regardless of the position of the movable element during its movement along the track, wherein the supporting member is mounted for rotation about a substantially horizontal axis in the movable element, and wherein the device for main¬ taining the supporting member in the predetermined posi- tion comprises an actuating mechanism connected with the supporting member, and a guide track arranged wholly or partially along the stationary track to interact with the elements in the actuating mechanism. There are applications for conveyors of this type for the transportation of goods in a predetermined posi¬ tion along a track which extends for example between different dwellings in a building. As examples of such transportation we can mention the transportation of pro¬ ducts within a factory between different production sta- tions and the conveyance of ready-laid trays in hospi¬ tals and similar service arrangements between a central kitchen and different wards. A conveyor of the type mentioned above is known previously from DE-OS 2429282 and more particularly re- lates to. the conveyance of batches of newspapers between different processing stations. This known conveyor has several disadvantages. Thus, the supporting member which has to be kept in a predetermined angular position during transportation along the stationary track is not reliab- ly positively-controlled in order to maintain the prede- ter ined (in this case vertical) position along the track. During a rapid transportation of the supporting member along the track in trolleys etc designed for this purpose there is accordingly considerable risk that the "locking mechanism" which is intended to main¬ tain the supporting member in the predetermined posi¬ tion will be affected by inertia forces in the event of a change in direction vertically such that the locking pins indicated by reference 18 in FIG 5 disengage the locking disc 16, whereby the supporting member is given an incorrect angular setting. This incorrect angular setting of the supporting member can also be achieved as a result of unauthorised actuation of the member by a force which is sufficient to change the position of the locking mechanism. The object of the present invention is to provide a conveyor of. the type referred to above, which can easily be run along an arbitrary path extending between different levels and having more or less complicated runs at each level , and in which the movable elements with the supporting members mounted thereon are reliab¬ ly and infinitely-variably controlled so as to positive¬ ly maintain the predetermined position of the supporting member in each position in the stationary track by means which require minimum maintenance and which eliminate the risk of inadvertent manipulation and the risk of the movable elements binding during their movement or jamming at any point along the movement path. With this object in view the conveyor in accordance with the invention has obtained the characteristics according to claim 1. In order to illustrate the invention some embodi¬ ments thereof will be described in greater detail in the following with reference to the accompanying drawings in w ich FIG 1 is a perspective view of a section of a con¬ veyor in accordance with the invention; FIG 2 is a front view of this section; FIGS 3 and 4 are enlarged vertical cross sectional views along the lines III - III and IV - IV in FIG 2; FIG 5 is a fragmentary front view, partially a ver¬ tical cross sectional view, of the conveyor; FIG 6 is a corresponding plan view, partially a horizontal cross sectional view, of the conveyor, FIGS 5 and 6 being on the same scale as FIGS 3 and 4; FIG 7 is a fragmentary front view, partly a verti¬ cal cross sectional view, of an alternative embodi- ment with locking arrangement; FIG 8 is a vertical cross sectional view along the line VIII - VIII in FIG 7; FIG 9 is a frontal view of a section of a conveyor in accordance with a modified embodiment of the invention; FIG 10 is a front view of a larger section of the conveyor shown in FIG 9; and FIG 11 illustrates a cross sectional view along the line XI - XI in FIG 9. The conveyor shown in FIG 1 comprises a stationary track in the form of a slotted box profile 10 with rear wall 11, upper wall 12, lower wall 13 and two front walls 14 which are in the same plane but are spaced so that they confine a slot 15 which extends along the box pro- file. This box profile can be assembled with the rear wall 11 fixed against a wall in a building or can be supported in stationary fashion in some other way. It can be curved in the vertical o r horizontal direction so as to follow the desired transportation path which can extend between different levels and on each level can deflect to one or other- side in an arbitrary pattern. Inside the box profile 10 a number of movable ele¬ ments in the form of trolleys 16 are guided, which are connected together by means of links 17 to form an end- less chain. Each trolley 16 comprises a plate 18 of rectangular shape which is provided at each corner with a welded-on bearing member 19. In a slot 20 in each bearing member a support roller 22 is rotably mounted by means of a shaft 21, said roller being arranged to run against the upper and lower walls 12 and 13,respec- ively, and on the outside of the bearing member a roller bearing 23 is provided which is mounted on the bearing member by means of a lock ring 24 and is designed to run against the rear wall or the front walls 11 and 14, respectively. Thus, by means of the rollers 22 and 23 the trolley is guided for movement along the box. profile 10 inside this, resting against the box profile walls on the inside thereof to the extent required dependent on the extension of the track. At both ends each link 17 is designed as a fork 25 which straddles the edge of the plate 18 and which is connected to the plate by means of a universal joint 26, as shown in FIG 6, so that the trolleys are free to move relative to each other without being impeded by the connection between them provided by the links. A cylindrical device 27 with an end wall 28 is rotably mounted in a circular aperture centrally in the rectangular plate 18. Mounting is provided by means of two lock rings 29 which are accommodated in grooves 30 in the member 27 on each side of the plate 18 and which hold two rings 31 against the opposite sides of the plate with inserts of plain bearing rings 32 made for example of Nylon between the rings 31 and the plate. Between the cylindrical member 27 and the plate 18 a cylindrical plain bearing bushing 33 made for example "gU E of Nylon is arranged. The end wall 28 which is connected with the member 27 supports centrally a shaft 34 which projects axially from the end wall, the shaft forming the supporting member for a plate 35 which is fastened to the shaft in a recess 36 in the free end thereof. Inside the cylindrical member 27 a cylindrical gear wheel 37 is rotably mounted, having chamfered ends 38 on the gears, and the shaft 39 of this gear wheel is transverse to the shaft 34 and thus to the rotational axis of the member 27 and it is also transverse to the plane of the plate 35. To permit engagement with the gear wheel a rack 40 is arranged on the inside of the rear wall 11 of the box profile 10, said rack extending along the rail with the teeth thereof all arranged ver- tically. When the trolley described above moves along the path formed by the box profile 10 with the gear wheel 37 engaging with the rack 40, the cylindrical member 27 which is rotably mounted in the plate 18 is constant- ly kept in a certain position in space with the plate 35 in the horizontal position, regardless of whether the trolley changes from the horizontal position to more or less vertical position. The gear wheel 37 is always maintained with the teeth vertical , since these engage the vertically arranged teeth on the rack 40. In a curve in the vertical direction the gear wheel 37, whilst simultaneously rolling against the rack 40, will be uni pededly moved in the vertical direction relative to the rack together with the trolley as this moves in the vertical direction, and when the trolley proceeds absolutely vertically, the gear wheel will not roll at all but instead will be displaced along the vertical teeth of the rack. Thus, the plate 35 is maintained constantly in the horizontal position regardless of the position adopted by the trolley, because the location of the plate is fixed as a result of the engagement between the teeth of the gear wheel 37 and the rack 40 in each position of the trolley along the track 10. In actual fact tooth guidance is required only in the curves made by the rails in the vertical direction, whilst guidance can be provided with other and simpler means in the absolutely vertical and the absolutely horizontal portions of the rail. Thus, on the end wall 28 there are pins 41 with rotably-mounted cam rollers 42. On the outside of the foremost walls 14 stationary angle profiles 43 are arranged, with one flange fastened to the walls 14, whilst the other flange projects from the angle profile, so that these flanges form a guide groove on the front of the box profile. At the ends of a vertical or horizontal section of the track 10 the flanges are arranged at an angle in respect of each other over shorter sections 43'. When a trolley arrives at the horizontal or vertical section with angle pro¬ files 43, the cam rollers 42 run in between the angle profiles the distance between the projecting flanges being so adjusted that the cam rollers .42, rolling against the flanges, keep the rotable device 27 in the predetermined angle of rotation. The guidance function is thus removed completely from the gear wheel/rack and accordingly the rack can in these sections be dispensed with completely, or perhaps also they can be maintained but made considerably narrower if it is wished to main¬ tain continuous tooth engagement over the entire length of the track. Instead of the cam guide means 41, 42, 43 a locking mechanism 141, 142, 143 can be arranged between the trolley 116 and the shaft 134 (FIGS 7 and 8). In this embodiment the trolley is shown built up from two side plates 118, which do not prevent the locking mechanism being employed in conjunction with the trolley described __ • _ • — in the preceding embodiment. FIG 7 illustrates the components forming part of the locking mechanism,' such as a detent hook 141, and a circular disc 142 with recesses 143 provided therein. The disc 142 is rotary together with the shaft 134. The detent hook 141 is loaded by means of the spring 146, so that the detent hook engages reliably the re¬ cess 143 when the trolley 116 adopts a horizontal or vertical position, or in transport paths where the in- clination is for example 45°, a position corresponding to this inclination. The function of the locking mechanism is as follows Just before the trolley 116 reaches a vertical rail radius, the gear wheel engages with the rack 140 (FIG 8). After reliable engagement has occurred and be¬ fore the rail radius starts a pulley 144 which is con¬ nected with the detent hook comes into contact with an entrance chamfer 145 of the rack whereby during the continued movement the detent hook is lifted to dis- engage the recess 143 so as to permit rotation of the shaft 134 which is connected with the disc, relative to the trolley 116. When the trolley has passed through the radius and started movement along a straight trans¬ portation section, there is again a chamfer on the rack which is opposite in direction to the chamfer initially mentioned (possibly supplemented by a short guide rail for active guidance on the pulley 144), as a result of which the detent hook 141 engages once more a recess 143. The rack ends directly after this, because at this stage of transportation it no longer carries out any function. Designs other than those described above can of course be utilised to bring about positive locking be¬ tween the shaft and trolley at predetermined angles of slope of the rail . The embodiment illustrated in FIGS 9 - 11 differs from the embodiments previously described mainly in that the rack 40 and the gear wheel 37 with its bearings are replaced by a guide track 243 with teeth designed to interact directly with an external adjustment device 242, 252 forming part of an actuating mechanism also comprising a reduction gear between the adjustment de¬ vice and the supporting member 34. To give an example of various embodiments which can be envisaged within the scope of the invention the track has been made open and consists of two tubes 213 which at a suitable spacing are held together by spacers 211. A track of this type can of course also be employed in the embodiment with rack initially described. The trolley 216 consists of two plates 218 which are held together partly by a central boss 244 and partly by a distance boss 245 and by two end tubes 246. U-shaped straps 246 are rotably mounted at each end of the latter. Each strap functions as a bearing for a runner wheel 222 having a shape adapted to suit the track formed by the two tubes 213. The hub 244 of the trolley 216 forms the mounting for the supporting member or shaft 34, on which a plate can for example be provided. An internally-toothed wheel rim 254 is fastened to the shaft 34, engaging a smaller gear wheel 248, the shaft 249 of which is mounted in the distance boss 245. A larger gear wheel 250 which engages with an internal gear wheel 251 mounted on the hub 244 is fastened to the same shaft. A roller holder 252 with four symmetrically arranged pins comprising mountings for four rollers 242 is fastened to the inner gear wheel 251. These rollers together with the roller holder 252 form a 4-toothed "gear wheel" which during the movement of the trolley along the track interact with a guide rail 243. As shown in FIG 10 this rail is straight along -fϋR .-- __ ■ the straight portions of the track and there interacts with two of the rollers 242 in such a way that the gear wheel 242 is fixed in its rotational position, provid¬ ing corresponding locking of the remaining components of the actuating mechanism, and thus also of the shaft 34. In upwardly-directed curves the guide rail or guide track 243 is designed as a gear rim. When the trolley passes along such a c urve the gear wheel 242 as a result of its engagement with the gear rim is forced to rotate. This rotational movement results in rotation of the gear wheel 251, the pair of gears 250, 248 and of the gear wheel 254 with the shaft 34 fastened therein. By suitable choice of pitch of the gear rim 243 and of the reduction ratio between the gear wheels 251/250 and 248/254, respectively, it is possible to obtain rotation of the shaft 34 which exactly compensates for the rotation .imparted to the trolley during its passage along the curved track. In a manner similar to that described above the trolleys 216 are held together so as to form an endless chain by means of links 217 and possibly intermediate trolleys 253. Naturally the "gear wheel" 242 can be designed in the same way as a conventional gear wheel with several teeth. By selecting only four teeth however, two of these can advantageously be employed also for guidance along the straight portions of the track. Driving of the endless chain can be brought about by automatically engaging for drive purposes the trolleys with an endless pulling device which extends along the straight portion of the conveyor path or, in the case of the embodiment of the conveyor initially described, by virtue of the fact that the gear wheels 37 are pro- vided with drive motors, at least on some trolleys. v. ι_ The invention is not limited to the embodiments illustrated here; modifications can be made within the scope of the following claims.

Claims: CLAI MS 1. Conveyor comprising a stationary track (10; 110; 213) the extent of which comprises sections at different levels, movable elements (16; 116; 216) which are guided by the track for movement along this, a supporting member (34; 134) on at least some of the movable members, and a device (37, 40; 140; 242, 243, 248 - 252, 254) for maintaining the supporting member in a predetermined angular position regardless of the position of the movable element during its movement along the track, wherein the supporting member (34; 134) is mounted for rotation about a substantially horizontal axis in the movable element (16; 116; 216), and wherein the device for maintaining the supporting member in the predetermined position comprises an actuating mechanism (37, 42; 242, 248 - 252, 254) connected with the support¬ ing member, and a guide track (40; 43; 243) arranged wholly or partially along the stationary track to inter- act with the elements (37; 42; 242) in the actuating mechanism, c h a r a c t e i s e d in that the actuat¬ ing mechanism (37, 42; 242, 248 - 252, 254) connected with the supporting member is arranged on the one hand to lock the supporting member in the predetermined angu- lar position when the movable member (16; 116; 216) is moving linearly along the track, and on the other hand to infinitely-variably adjust the supporting member so as to maintain its predetermined angular position when the movable member is moving along the track and being subjected to a vertical change in direction. 2. Conveyor in accordance with claim 1, c h a r a c t e r i s e d in that the actuating mechanism comprises a member in the form of a cylindrical gear wheel (37), which is mounted for rotation about an axis transverse to the axis of rotation of the supporting member (34), and interacts with the guide track, the latter consisting at least partially of a rack (40). 3. Conveyor in accordance with claim 1, c h a r a c t e s e d in that the actuating mechan- ism comprises several roller members (242) placed symme¬ trically around the supporting member (34) on a roller holder (252) for interaction with the guide track (243), an inner gear wheel (251) fastened to the roller holder (252), a further pair of gear wheels (250, 248) with one larger and one smaller gear wheel mounted in the movable member (216), the larger wheel (250) engaging the inner gear wheel (251) and the smaller gear wheel (248) engaging an internally-toothed wheel rim (254) which is secured to the supporting member (34), the guide track being at least partially formed by a gear track, the pitch of the gear track and the transmission ratio between the gear wheels (251 and 250, and 248 and 254, respectively) being selected such that the rota¬ tion of the supporting member (34) corresponds to the rotation of the movable element (216) during its move¬ ment accompanied by a vertical change in direction along the stationary track (213). 4. Conveyor in accordance with claim 1, c h a r a c t e r s e d in that a locking mechanism (141 - 143) is located between the supporting member (134) and the movable member (116), which is arranged such that it maintains locking against rotation between the supporting member and the movable element during the movement of the movable element along straight portions of the stationary track (110). 5. Conveyor in accordance with claim 4, c h a r a c t e i s e d in that the locking mechanism comprises a disc (142) with peripheral recesses (143) fastened to the supporting member (134), and a detent hook (141) mounted on the movable element (116) and designed to engage such a recess. 6. Conveyor in accordance with claims 4 and 5, c h a r a c t e r i s e d in that a member (144) asso¬ ciated with the detent hook (141) is arranged to inter¬ act with a member (140) arranged at the track (110) so as to disengage the locking mechanism at vertical curves in the track. 7. Conveyor in accordance with claim 6, c h a r a c t e r i s e d in that the element (140) for disengaging the locking mechanism comprises a guide sur¬ face on the guide track, being a rack (110), the guide surface being provided with an entry chamfer (145) and possibly an exit chamfer. . u

Inventors: PERSSON I, PERSSON P
Applicants: IFOE KAMPRI AB, PERSSON I, PERSSON P
Application year: 1980
Main classification: B65G17
IPC codes: B65G17, B65G21