1. Field of the Invention
The present invention relates to a method and an apparatus for taking out laundry articles from a laundry pile, wherein a minor batch of laundry articles is seized by a pull gripper intended therefor and pulled out of the laundry pile and lifted clear above the same.
2. Description of the Related Art
Such machines are known today for use in e.g. industrial laundries where the laundry articles, such as bedclothes and cloths which are, for instance following washing and tumble drying, in a more or less entangled pile, in a damp state.
These laundry articles are subsequently to be introduced individually into machines intended e.g. for straightening, ironing and folding the laundry articles.
In the laundries, it is thus a task to separate the laundry articles from the pile in which they are following washing and tumble drying in order to allow them to be introduced in to the subsequent machines for e.g. straightening, ironing and folding.
Today this process is carried out more or less manually but efforts are made to increasingly automate the process, the work positions involved in the manual process being quite straining, and therefore machines have already been developed to carry out at least some steps of the process automatically.
Such machines are known from e.g. DE 43 30 911 which features an arrangement consisting of two separate grippers which may cooperate to take out an individual laundry article from the laundry pile and thus to convey the individual laundry article to the subsequent machinery. The grippers in the known machine are so arranged that the gripper which pulls the individual laundry article out of the laundry pile has been optimised accordingly, whereby the gripper seizes a. comparatively small corner or a comparatively small portion of the laundry article with a view to ensuring that the gripper takes out only one laundry article from the pile.
It is a problem, however, with these prior art machines that the laundry articles in the laundry pile are often very entangled as a consequence of the washing and drying processes, and that this is enough to require a powerful pull in the laundry articles in order to separate them from the pile, Which is further aggravated by the fact that frequently the laundry articles are slightly damp whereby the friction between the laundry articles is often increased. This may mean that the gripper which takes out the laundry article from the pile is incapable of performing this task in a satisfactory manner since, advantageously, the seizing force and seizing area of the gripper is as small as possible as it is desired to ensure to the highest degree possible that the laundry articles are taken out of the pile individually. If the seizing force is increased, tearing of the laundry articles may as it is desirable to have a small seizing area.
In practice this may mean that the gripper cannot take out any laundry articles whatsoever which would require interference from an operator or readjustment of the machine.
U.S. Pat. No. 4,943,198 features an apparatus for automatically taking out laundry articles from a laundry pile whereby automation of this step of the process is allowed, and whereby it is ensured to a higher degree that no operational stoppages or tearing of the laundry articles occur.
This is obtained by a smaller batch of laundry articles being pulled out of the laundry pile by a gripper intended therefor, following which this minor batch of laundry articles is taken away from the laundry pile and conveyed above a support, following which the laundry articles are deposited on the support. This minor batch of laundry articles will then be significantly less entangled than it was in the pile following e.g. washing and tumbling, thereby facilitating the subsequent taking out of individual laundry articles from this minor batch of laundry articles substantially.
The pull gripper may thereby be so designed that it seizes a large portion of the laundry articles and in a powerful manner, since there is no requirement that the gripper takes out one single laundry article at a time from the pile. When more laundry articles are taken out at a time it follows that the risk of tearing the individual laundry article is also reduced.
Since the method and apparatus according to U.S. Pat. No. 4,943,198 deal with the desire to ensure that only one single laundry article is taken out at a time, more room is left for providing such convenient pull gripper as to ensure that laundry articles are always taken out from the pile with no regard to the quantity.