IMPROVEMENTS IN OR RELATING TO LAUNDRY ARTICLE HANDLING APPARATUS

Abstract: The disclosure relates to a laundry article handling apparatus comprising at least one article clamp (27) having fluid pressure operated means (29) for closing the clamp to hold an article therein, means (26, 26a) for moving the clamp between an article receiving and article release positions, a source of pneumatic pressure (43) having outlet means (36) disposed at said article receiving position, the pneumatic pressure operated means (37) to cooperate with said outlet means (36) and having means (44) to retain the pneumatic pressure supplied thereto to hold an article in the clamp when separated from the outlet means (36). Release means (45, 46, 47) are provided to release pneumatic pressure from the pressure operated means (29) to allow the article to be released from the clamp with actuating means (60) at the release position for operating the release means.

Description: This invention relates to laundry article handling apparatus and in particular to apparatus for feeding laundry articles (usually flat-work articles such as bed-sheets, tablecloths, pillow cases and the like) to machines for further processing of the articles such as ironing machines. Conveyors are commonly used in such applications with automatic feeding systems to lay the laundry articles to be processed onto the conveyor for feeding to the requisite further processing equipment (e.g. a commercial ironer). Such feeding systems may comprise carriages movable along guideways and carrying clipping means for gripping adjacent corners or edges of the particular article. When the carriages, each with its respective clipping means, are drawn apart, the leading edge of the article is centred and stretched across the conveyor entry. Subsequently, the article is released from the clipping means and transferred over the inlet end surface of the automatic feeding conveyor by a transfer mechanism. Several devices are known in the art which centre and spread laundry on an automatic feeding conveyor. These devices achieve accurate centring of laundry articles by employing clipping means contained in movable carriages as indicated above. The carriages in those prior art devices start from a position located at either side or centre of the conveyor. The carriages synchronously move in outward directions from the conveyor centre until the entire leading edge of the laundry article has been fully extended and centred over the conveyor surface. FR-A-1513669 and US-A-4106227 disclose typical examples of such laundry article conveyor feeding systems. A major disadvantage of these prior art devices is the large number of parts and elements employed in achieving the fast and accurate centring and spreading of laundry articles. Because of this complexity, problems are incurred in both the maintenance and replacement of such devices. As a result, the prior art devices are necessarily costly both to operate and maintain and are not as reliable as a more simplified apparatus. This invention provides a laundry article handling apparatus comprising at least one article clamp having fluid pressure operated means for closing the clamp to hold an article therein, and means for moving the clamp over a range of travel between article receiving and article release positions; wherein a stationary source of pneumatic pressure having outlet means is disposed at said article receiving position, in that the pneumatic pressure operated means of the clamp has inlet means to co-operate with said outlet means when in the article receiving position, means to retain the pneumatic pressure supplied thereto to hold an article in the clamp when separated from the outlet means and release means to release said pneumatic pressure and thereby release an article from the clamp, and wherein actuating means are provided for the release means operable over said range of travel of the clamp from said article receiving position to release the clamp when it reaches a requisite release position. In one arrangement according to the invention two of said clamps are provided to receive and hold corners of an article to be spread open, said outlet means communicating with the inlet means for the pneumatic pressure operated means of both clamp means in said article receiving position, said clamp moving means are arranged to move the clamps between adjacent receiving positions and spaced apart positions to spread the article held by the clamps and said actuating means releases the clamps in their spaced apart positions to release the article thus spread. In the latter arrangement said clamp moving means may move the clamps simultaneously together to said article receiving positions and simultaneously apart to said article release positions. Futhermore the clamp moving means may be adjustable to enable the distance moved by the clamps from the receiving positions to the release positions to be varied to suit the size/shape of the article to be spread thereby. In the preferred arrangement of the invention the actuating means for releasing air pressure from the clamps extends over the range of travel of the clamps to release the clamps wherever they reach after spreading the article supported thereby. In any of the preceding claims means may be provided for guiding the clamp or clamps for linear movement. In the latter arrangement the linear guide means may comprise linearly extending track means to mount the clamp or clamps for movement along the track means. In an alternative arrangement means may be provided for guiding the clamp or clamps through a non-linear path between said article receiving and article release positions. In the latter case the means for guiding the clamp or clamps may be arranged to guide the clamp or clamps through a rotary path between said article receiving and article release positions. More specifically the means for guiding the clamp or clamps may comprise an endless conveyor for guiding the clamp or clamps through said rotary path. In any of the above arrangements in which a pair of clamps is provided, said source of pneumatic pressure may have a common air supply for communication with the respective inlets of the two clamps and means may be provided for controlling said air supply. In one arrangement according to the invention said source of pneumatic pressure may have separate outlets for the respective inlets of the clamps each outlet having an independently operable control means. In either of the latter arrangements the pneumatic pressure operating means of the clamps may have projecting nozzles which, in the receiving positions of the clamps, align with and engage in corresponding sockets in the outlet means of the pneumatic pressure supply to receive air under pressure therefrom. In the latter case the sockets of the outlet means may face in opposite directions from the receiving station to receive projecting nozzles of the pneumatic pressure operated means for the clamps. In a further arrangement said source of pneumatic pressure at the article receiving position may be mounted for movement towards and away from said path to engage with and detach from the pneumatic pressure operated means of the clamp when the clamp or clamps are in the article receiving position. Said control valve means may be arranged to supply air under pressure thereto when the clamp or clamps are engaged therewith and to close off the pneumatic pressure supply before the clamp or clamps separate from the outlet means. The following is a description of some specific embodiments of the invention, reference being made to the accompanying drawings, in which: FIGURE 1 is a front elevation view of part of a laundry flatwork feeding apparatus; FIGURE 2 is a side elevation view of part of the apparatus shown in Figure 1; FIGURE 3 is a detailed view of part of a pneumatic feed system for the apparatus of Figures 1 and 2; FIGURE 4 is a diagrammatic view of a pneumatic circuit for the apparatus of Figures 1 to 3; FIGURE 4A is a detailed view of a part of the apparatus indicated by the arrow 4A on Figure 1; FIGURE 4B is a detailed view indicated by the arrow on Figure 4A; FIGURES 5 and 6 illustrate other forms of circuit; and FIGURES 7 and 8 illustrates the application of the invention to a further construction of feeding apparatus. The improvements in laundry article handling apparatus to which the present invention relates are applicable generally to laundry article spreading apparatus such as that described and illustrated in my U.S. patent No. 4411083 to which reference should be made. The latter specification discloses an apparatus for centring and spreading laundry articles on the conveyor of a machine, automatically feeding such articles to a commercial laundry iron and comprises lead and trailing carriages having clipping apparatus for clipping adjacent corners of such articles, a track to convey the carriages, and a belt driven by a motor for moving the carriages on the track. The corners of a sheet or other article are attached to the clipping means of the respective carriages with the carriages in close proximity and the motor drive for the carriages is then actuated to separate the carriages and thereby spread the edge of the sheet spanning the corners ready to be fed into the apparatus. Referring now to Figure 1 and 2 of the drawings, there is shown an article handling apparatus to be disposed in front of a delivery system (not shown) for feeding articles to a subsequent processing station such as an ironing machine. The apparatus comprises a supporting framework indicated generally by the reference numeral 10 on which an elongate track is mounted comprising a horizontal flange 11 supported by means of an upright leg 12 on a part of the framework and cylindrical tube 13 mounted on another part of the framework 10 and extending parallel to the flange. The flange 11 and tube 13 form, between them, a track on which a pair of carriages 14 are mounted for linear displacement. Each carriage comprises a pair of interconnected upper and lower horizontal plates 16,17 of inverted channel-section form. Two pairs of diabolo-shaped wheels 18,19 are mounted for rotation between the upper and lower plates at spaced locations along the plates to engage and run along the cylindrical tube 13. A vertical plate 20 is secured mid-way along one side of the pair of channels to project below the channels. A pair of upper and lower wheels 21,22 are mounted to rotate about spaced horizontal axes 22,23 on hubs 24 one secured to the plate 20 between the channels and the other to the past of the plate depending below the chnnels. The wheels engage the upper and lower sides of the aforesaid horizontal flange 11 of the track. The carriage 14 is thus guided and constrained for linear horizontal movement along the track formed by the flange 11 and cylindrical tube 13. The two carriages 14 are displaced linearly along the track from positions immediately to either side of a centre line indicated at 25 on Figure 1 and spaced positions towards the respective ends of the track by a double-acting pneumatic cylinder 26 mounted on the frame 10 and having a piston rod 26a connected through a system endless belts to multiply movement of the rod to the respective carriages to move the carriages towards and away from each other along the track. Each carriage has a pneumatically operated clamp indicated generally at 27 on Figure 2 for securing a corner of a sheet thereto. The clamp comprises a base member 15 secured by brackets 15a to the lower channel 17. The member is formed with one down turned clamp jaw 28. A housing 30 is secured to the underside of base member 15 in which a pneumatic ram 29 is mounted. The ram has a piston rod 31 projecting from the cylinder thereof to which a movable jaw 32 is connected to move towards and away from fixed jaw 28. Pneumatic pressure supplied to the cylinder 29 extends the piston rod 31 to engage the movable jaw with fixed jaw 28 to trap a corner of the sheet disposed therebetween. An external tension spring 33 extends between the movable jaw 32 and a fixed anchorage 34 on the cylinder 29 to cause the ram to retract when air pressure is released from the cylinder and thereby release a sheet corner from the clamp. The spring 33 could of course be embodied internally in the cylinder or a double acting cylinder could be utilised. Each carriage 14 has an injection probe 35 mounted on the carriage on the side thereof facing the centre 25 of the track and connected by a non-return valve as described below to the rear of the cylinder 29. As best seen in Figures 1 and 3, an air injection gland or dock 36 is mounted at the centre of the apparatus on a fixed member 37 of the apparatus and has ports 38,39 facing in opposite directions along the carriage track to receive the respective probes 35 on the carriages when the carriages are adjacent the centre of the track. The ports 38 each have internal seals 40 to cooperate with the probes. Referring now to the pneumatic circuit of Figure 4, the gland 36 is connected via pneumatic lines to an air pressure supply through a solenoid controlled valve 42. The solenoid controlled valve 42 is operated by a control system indicated diagrammatically at 43 which may include a programmable micro-processor control system. The probes 35 are connected to the respective cylinders 29 through non-return valves 44 and pressure release valves 45 for releasing air pressure from the cylinders 29 to atmosphere. Each valve 45 is of conventional design having a projecting plunger 46 operable by a pivotally mounted strikers 47 on the valve body. An elongate cam 60 extends the length of the track adjacent the path of the valves 45 on the carriages 14 and is mounted to pivot about a horizontal axis 61 extending along one edge of the cam in end mountings 62. As illustrated in Figure 4A and 4B, at the centre of the cam there is a lever 63 extending laterially of the cam and a vertically acting pneumatic cylinder 64 has a plunger 65 to engage the lever to pivot the cam upwardly to engage the strikers 47 of the valves 45 to open the valves and thereby release air pressure from the respective cylinders 29. Thus, when the carriages 14 are adjacent the centre 25 of the guide track, air pressure can be supplied from the source through the gland 36 and through the respective probes 35 of the carriages to the cylinders 29 to cause the cylinders to extend and engage the pressure pads thereof with the legs 28. The corners of a sheet to be spread and centred utilising the apparatus are held captive on the respective carriages. Having engaged the respective corners of the sheet with the clamps, the air supply to the gland 36 is switched off and the pneumatic ram for moving the carriages is energised to displace the carriages towards opposite ends of the track to spread the upper edge of the sheet. The pressure in each cylinder 29 is maintained to hold the corners of the sheets in the clamps by reason of the non-return valves 44. When the sheet has been fully spread and is ready for the next feeding movement from the spreading apparatus, the cam is pivotted to trip the strikers 47 of valves 45 to release air from the cylinders 29. The return springs 33 for each of the cylinders retract the movable clamp jaws 32 thereby releasing the corners of the sheet to allow the sheet to be moved onwards in its spread condition to the next stage of the feeding apparatus. The apparatus described above is particularly suitable for use with an "automatic transfer loading system". This is where the clamps are themselves loaded by another mechanism comprising a pair of clips into which the operator has previously loaded the corners of the article. When the clips introduce the corners of the article into the clamps, both clamps are closed simultaneously. Figure 5 shows a variant of the apparatus suitable for manual loading of the clamps by an operator. Generally, the system is the same as that shown in Figure 4 except that the clamps 29 are arranged to be operable independently and the gland 36 has separate air feeds 50 to the respective ports 38,39 to receive the probes of the clamps. Each air supply 50 has a solenoid control valve 51 connected in a circuit indicated generally at 52 having separate switches 53 for the respective solenoid valve. The switches 53 could of course be replaced by manually operated air valves. Such air valves could be hand triggered or foot controlled. In the above arrangement, the clamps have docked with a centrally positioned gland on the track and the main compressed air feed outlet to close the clamps is located at the central gland or dock in a position in line with the inlet probes of the respective carriages. When the carriages are moved to the central loading position, the inlet couplings engage with the stationary outlet sections and compressed air can be fed to close the clamps. when the carriages are moved away from the centre, the supply is disconnected. In a further arrangement, "side" docking is provided in which the two clamps and their respective carriages are mounted on a track both being arranged to move to one end of the track for loading. This system permits the use of dual clamping mechanisms as described above sharing a common track with one station at each end. The compressed air feed outlets are located in a side dock or gland situated at each end of the track. The inlet probes on the movable carriages are arranged to align with the feed outlets of the glands and to connect with them when the carriages are moved to their loading positions. Figure 6 shows a further variant in which the movable carriages supporting the clamps and circuits make direct contact with the air supply outfeed when they are moved into their loading positions and an "auto engage entry" is provided for use when it is necessary to engage and disengage the air feed from the clamp mechanisms by moving the outlet feed 51,53 to engage with the movable inlet couplings 38. This method must be used in the rotary docking system which is now described. In a further "rotary" docking arrangement illustrated diagrammatically in Figures 7 and 8, pairs of pneumatically operated clamp mechanisms 27 are supported on beams 60 (or tracks if the clamps in each pair are to move towards and away from one another) which are, in turn, supported at spaced locations on a conveying means comprising a pair of spaced apart endless chains or toothed belts 61. The chains extend around spaced sprockets 62 one of which is driven by a motor through an indexing mechanism to advance the conveyor in predetermined steps to move the clamp carrying beams between a loading station 63 and a delivery station 64 spaced apart around the conveyor. The clamps 29, together with the non-return valves 44, release valves 45 and inlet probes 35 are all mounted on the beams 60 with the probes projecting outwardly of the conveyor sides. Air glands or docks 36 for the respective clamps are mounted to either side of the conveyor mechanism at the loading station 63 as best seen in Figure 8 on spring retracted pneumatic rams 65 connected through solenoid controlled valves 42 to a compressed air supply. The valves 42 have outlet ports connected to both the air glands 36 and to the pneumatic rams. Thus, when valves 42 are opened, air is supplied to the rams 65 which extend and engage the glands 36 on the probes 35. At the same time air is supplied through the glands/probes to the pnematically closed clamps 27 to hold an article therein. Valves 42 are then set to vent to atmosphere release air pressure to the rams 65 which then retract the glands 35 from the probes. The non-return valves 44 hold the charge of air pressure supplied to the clamps which therefore remain closed. The next indexing movement of the conveyor mechanism brings the beam 60 into register with the delivery station 64 where a fixed plate 66 engages the strikers 47 of the pressure release valves 45 of the clamps to vent the rams of the clamps to atmosphere to allow the clamps to open. An article held therein is then allowed to transfer to a feed conveyor 67. Further details of the apparatus for transferring the article from the clamping/spreading apparatus described above to the ironing or other further processing apparatus are to be found in GB-A-8813109.9 and GB-A-8813110.7.

Claims: A laundry article handling apparatus comprising at least one article clamp (27) having fluid pressure operated means (29) for closing the clamp to hold an article therein, and means (26) for moving the clamp over a range of travel between article receiving and article release positions; characterised in that; a stationary source of pneumatic pressure having outlet means (36) is disposed at said article receiving position, in that the pneumatic pressure operated means of the clamp has inlet means (35) to co-operate with said outlet means when in the article receiving position, means (44) to retain the pneumatic pressure supplied thereto to hold an article in the clamp (27) when separated from the outlet means and release means (45,46,47) to release said pneumatic pressure and thereby release an article from the clamp, and in that actuating means (60,61,62) are provided for the release means operable over said range of travel of the clamp from said article receiving position to release the clamp when it reaches a requisite release position. An article handling apparatus as claimed in Claim 1, characterised in that two of said clamps (27) are provided to receive and hold corners of an article to be spread open, said outlet means communicating with the inlet means for the pneumatic pressure operated means of both clamp means in said article receiving position, in that said clamp moving means (26) are arranged to move the clamps between adjacent receiving positions and spaced apart positions to spread the article held by the clamps and in that said actuating means (60,61,62) releases the clamps in their spaced apart positions to release the article thus spread. An article handling apparatus as claimed in Claim 2, characterised in that said clamp moving means (26) moves the clamps simultaneously together to said article receiving positions and simultaneously apart to said article release positions. An article handling apparatus as claimed in Claim 2 or Claim 3, characterised in that the clamp moving means (26) is adjustable to enable the distance moved by the clamps (27) from the receiving positions to the release positions to be varied to suit the size/shape of the article to be spread thereby. An article handling apparatus as claimed in any of Claims 2 to 4, characterised in that the actuating means (60) for releasing air pressure from the clamps extends over the range of travel of the clamps (27) to release the clamps wherever they reach after spreading the article supported thereby. An article handling apparatus as claimed in any of Claims 1 to 5, characterised in that means (11,13) are provided for guiding the clamp or clamps for linear movement. An article handling apparatus as claimed in Claim 6, characterised in that the linear guide means comprises linearly extending track means (11,13) and means (21,16) to mount the clamp or clamps for movement along the track means. An article handling apparatus as claimed in any of Claims 1 to 5, characterised in that the means (26) are provided for guiding the clamp or clamps through a non-linear path between said article receiving and article release positions. An article handling apparatus as claimed in Claim 8, characterised in that the means for guiding the clamp or clamps (27) is arranged to guide the clamp or clamps through a rotary path between said article receiving and article release positions. An article handling apparatus as claimed in Claim 9, characterised in that the means for guiding the clamp or clamps comprise an endless conveyor (61) for guiding the clamp or clamps through said rotary path. An article handling apparatus as claimed in any of Claims 2 to 10, characterised in that said source of pneumatic pressure has a common air supply (36) for communication with the respective inlets (37) of the two clamps (27) and means (42) are provided for controlling said air supply. An article handling apparatus as claimed in any of Claims 2 to 10, characterised in that said source of pneumatic pressure has separate outlets (36) for the respective inlets (35) of the clamps each outlet having an independently operable control means (42). An article handling apparatus as claimed in Claim 11 or Claim 12, characterised in that the pneumatic pressure operating means of the clamps (27) have projecting nozzles (37) which, in the receiving positions of the clamps, align with and engage in corresponding sockets (38, 39) in the outlet means (36) of the pneumatic pressure supply to receive air under pressure therefrom. An article handling apparatus as claimed in Claim 13, characterised in that the sockets (38,39) of the outlet means (36) face in opposite directions from the receiving station to receive projecting nozzles (37) of the pneumatic pressure operated means for the clamps (27). An article handling apparatus as claimed in any of Claim 11 to 14, characterised in that said source (36) of pneumatic pressure at the article receiving position is mounted for movement towards and away from said path to engage with and detach from the pneumatic pressure operated means of the clamp (27) when the clamp or clamps are in the article receiving position. An article handling apparatus as claimed in any of the Claims 11 to 15, characterised in that said control valve means (42,43) is arranged to supply air under pressure thereto when the clamp or clamps (27) are engaged therewith and to close off the pneumatic pressure supply before the clamp or clamps separate from the outlet means.

Inventors: WEIR, HENRY JOHN
Applicants: WEIR, HENRY JOHN
Application year: 1989
Main classification: D06F67
IPC codes: D06F67