Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
FOLDING DEVICE FOR FOLDING TEXTILE OR OTHER FOLDABLE MATERIAL
Document Type and Number:
WIPO Patent Application WO/2007/105949
Kind Code:
A2
Abstract:
The invention relates to a device for folding articles of foldable material (25), such as towels or pillowcases, wherein the articles comprise two article parts which are folded over each other, wherein the device comprises a frame, a transport element (7) which is placed in the frame and the width of which is at least as great as that of the first article part, and a first folding element (11) extending from the first side of the transport element to below or above the transport element for the purpose of forcing the second article part to a position respectively below or above the transport element, wherein the device comprises a first engaging element (13) which is placed on the first side of the transport element partially below or above the transport element and which is adapted to engage the first article part situated respectively below or above the transport element and to exert a pulling force on the first article part in the direction of movement of the transport element.

More Like This:
Inventors:
OERLEMANS JOHANNES JACOBUS MAR (NL)
Application Number:
PCT/NL2007/050099
Publication Date:
September 20, 2007
Filing Date:
March 12, 2007
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
OERLEMANS JOHANNES JACOBUS MAR (NL)
International Classes:
D06F89/00; A47B87/02; A47F1/12
Foreign References:
GB516222A1939-12-28
US3829081A1974-08-13
Attorney, Agent or Firm:
EVELEENS MAARSE, Pieter et al. (BN 's-Hertogenbosch, NL)
Download PDF:
Claims:

Claims

1. Device for folding flat articles made of foldable material, such as towels or pillowcases, wherein the articles for folding comprise a first article part and a second article part and wherein the two article parts are folded over each other, wherein the device comprises:

- a frame;

- a transport element which is placed in the frame and the width of which is at least as great as that of the first article part; and - a first folding element extending from the first side of the transport element to below or above the transport element for the purpose of forcing the second article part to a position respectively below or above the transport element, characterized in that the device comprises a first engaging element which is placed on the first side of the transport element partially below or above the transport element and which is adapted to engage the first article part situated respectively below or above the transport element and to exert a pulling force on the first article part in the direction of movement of the transport element.

2. Device as claimed in claim 1, characterized in that the first engaging element is a movable engaging element which is drivable with a speed component in the direction of movement of the transport element which is at least as great as the speed of the transport element.

3. Device as claimed in claim 2, characterized in that the first movable engaging element comprises a first rotatable disc, which is provided on its periphery with a brush extending all around.

4. Device as claimed in claim 3, characterized in that the first rotatable disc is disposed with its main plane substantially horizontal, wherein the tangent of the first disc in the direction of movement corresponds with the projection of the edge on the first side of the transport element.

5. Device as claimed in any of the foregoing claims, characterized in that the first folding element is adapted to fold the second article part to a position below the transport element.

6. Device as claimed in any of the foregoing claims, characterized in that the device is adapted to fold over each other the first, the second and a third article part connected to the first article part, wherein the width of the transport element corresponds to that of the first article part,

- that the device comprises a second folding element for forcing the third article part to a position below or above the transport element, and

- that the device comprises a second engaging element which is placed on the first side of the transport element partially below or above the transport element and which is adapted to engage the third article part and to exert a pulling force on the third article part in the direction of movement of the transport element.

7. Device as claimed in claim 6, characterized in that the second engaging element is a movable engaging element which is drivable with a speed component in the direction of movement of the transport element which is at least as great as the speed of the transport element.

8. Device as claimed in claim 7, characterized in that the second movable engaging element comprises a second rotatable disc, which is provided on its periphery with a brush extending all around.

9. Device as claimed in claim 8, characterized in that the second rotatable disc is disposed with its main plane substantially horizontal, wherein the tangent of the second disc in the direction of movement corresponds with the projection of the edge on the second side of the transport element.

10. Device as claimed in any of the foregoing claims, characterized in that the second guide is adapted to fold the third article part to a position below the transport element.

11. Device as claimed in claim 9 or 10, characterized in that the diameter of each of the discs is greater than the width of the transport element, and that the second rotatable disc is placed behind the first rotatable disc in the direction of movement of the transport element.

12. Device as claimed in any of the foregoing claims, characterized in that the transport element comprises a folding template and a conveyor belt extending thereabove, wherein the conveyor belt is adapted to move the first part of articles for folding over the folding template.

13. Device as claimed in any of the foregoing claims, characterized in that the folding template comprises two strips, wherein the distance between the two strips can be changed.

14. Device as claimed in claim 13, characterized in that the device comprises a spindle which extends substantially transversely of the direction of movement of the transport element and which is adapted to displace the strip on the first side of the folding template.

15. Device as claimed in claim 14, characterized in that the first folding element comprises a part which extends above the first disc and the contour of which is adapted to the periphery of the first disc.

16. Device as claimed in any of the foregoing claims, characterized in that the transport element connects to a cross-folding device, and that the cross-folding device comprises:

- a supply element for supplying the folded articles in substantially horizontal direction;

- a guide element placed under the discharge end of the supply element, wherein the guide element is adapted to guide parts of the folded articles released from the supply element;

- a discharge element for discharging by means of engagement folded articles coming from the supply element and situated partially on the guide element;

- an activating element for forcing the folded articles into engagement with the discharge element; and

- a detection element for detecting the presence of a part of the folded article on the guide element and for activating the activating element when this presence is detected.

17. Folding device as claimed in claim 16, characterized in that the discharge element comprises two conveyor belts, and that the activating element comprises a blow nozzle leading to the point of engagement between the conveyor belts.

18. Folding device, characterized by more than one cross-folding device as claimed in claim 16 or 17.

19. Method for folding articles made of foldable material, such as towels, comprising the following steps of:

- placing the articles for folding partially into engagement with a transport element;

- transporting the articles with the transport element, wherein parts of the articles not in engagement with the transport element are forced by at least a first folding element extending from a side of the transport element to below or above the transport element to a position respectively below or above the transport element, characterized in that after covering a certain path, parts of the articles for folding not in engagement with the transport element are engaged by at least one engaging element, and wherein the engaging element exerts a pulling force, in the direction of movement of the transport element, on the relevant part of the article for folding.

20. Method as claimed in claim 19, characterized in that the engaging element is driven at a speed in the direction of movement of the transport element which is at least as great as that of the transport element.

21. Method as claimed in claim 19 or 20, characterized in that the articles are carried from the transport element to a cross-folding device, and that in the cross- folding device the parts of the folded articles released from the discharge end of the supply element are fed to a guide element and that, when reaching a position on the guide element, the articles are carried into engagement with a discharge element by activating an activating element and are subsequently discharged by the discharge element.

Description:

Folding device for folding textile or other foldable material

The invention relates to a device for folding flat articles made of foldable material, such as towels, pillowcases or items of clothing such as hospital gowns, wherein the articles for folding comprise a first article part and a second article part and wherein the device comprises a frame, a transport element which is placed in the frame and the width of which is at least as great as that of the first article part, and a first folding element extending from the first side of the transport element to below or above the transport element for the purpose of forcing the second article part to a position respectively below or above the transport element.

Such a device is known from US-A-3 829 081.

This prior art folding device is only provided with a folding element for guiding and folding that part of the article that must be folded. This means that as a consequence of the friction forces the article part for folding is pulled askew, and the resulting fold is generally misoriented.

The present invention has for its object to obviate this problem.

This objective is achieved in that the device comprises a first engaging element which is placed on the first side of the transport element partially below or above the transport element and which is adapted to engage the first article part situated respectively below or above the transport element and to exert a pulling force on the first article part in the direction of movement of the transport element.

As a result of this measure the article part to be displaced for the purpose of folding is not only driven by the transport element but also by the engaging element. This engaging element generates a force extending substantially in the direction of movement of the transport element, thus avoiding the danger of the second article part being pulled askew and, as a result, a misoriented fold.

It is noted here that it is known from EP-A-O 881 322 to fold an article by means of blowing with air. This operation can however only be initiated once the whole article

has been placed in the relevant device. This generally requires long devices. In the above stated US-A-3 829 081 it is possible to suffice with a shorter device, although there is the above mentioned drawback of a misoriented fold.

The invention likewise relates to a method for folding articles made of foldable material, such as towels, wherein the method comprises the steps of placing the articles partially into engagement with a transport element using positioning means, transporting the articles with the transport element, wherein parts of the articles not in engagement with the transport element are forced by a first folding element extending from a side of the transport element to below or above the transport element to a position respectively below or above the transport element whereby, after covering a certain path, parts of the articles not in engagement with the transport element are engaged by an engaging element, and wherein the engaging element exerts a pulling force on the relevant article part in the direction of movement of the transport element.

According to a first preferred embodiment, the first engaging element is a movable engaging element which is drivable with a speed component in the direction of movement of the transport element which is at least as great as the speed of the transport element. As a result of these mechanical properties the chance of pulling askew and misoriented folding are decreased still further.

The construction of the engaging element is simplified when the first movable engaging element comprises a first rotatable disc, which is provided on its periphery with a brush extending all around.

The effectiveness of the disc and the simplicity of the construction are further simplified when the first rotatable disc is disposed with its main plane substantially horizontal and when the tangent of the first disc in the direction of movement corresponds with the projection of the edge on the first side of the transport element.

A fold can be obtained by folding the second article part to a position above the first article part, as is otherwise known per se from US-A-3 980 290, although it is mechanically attractive for the first guide to be adapted to fold the second article part to

a position below the transport element. Use can after all be made here of the force of gravity.

The above described embodiments are adapted to make a single fold, so that a folded article results with two layers and a single fold. It may be desirable, particularly in the case of large articles, to apply more layers. For this purpose a further embodiment provides the measure that the device is adapted to fold the first, the second and the third article part over each other, wherein the width of the transport element corresponds to that of the first article part, wherein the device comprises a second folding element for forcing the third article part to a position below or above the conveyor belt and wherein the device comprises a second engaging element which is placed on the first side of the transport element partially below or above the transport element and which is adapted to engage the third article part and to exert a pulling force on the third article part in the direction of movement of the transport element. With this device it is possible to fold a sheet into a three-layer structure.

Measures applied in the single-fold embodiment are preferably also applied in this embodiment.

So that the discs can be in contact with the article part over a long path and exert a sufficiently great force while running through this path, it is necessary for the discs to have a large diameter. When the diameter of each of the discs is greater than the width of the transport element, it is recommended that the second rotatable disc is placed behind the first rotatable disc in the direction of movement of the transport element.

As elucidated above, it is attractive that the second and optionally the third article part are folded from below against the first article part already extending horizontally. It is then attractive to make the distance between the initial horizontal first article part and the upward folded article parts as small as possible. This is preferably achieved in that the transport element comprises a folding template and a conveyor belt extending thereabove, wherein the conveyor belt is adapted to move articles for folding over the folding template. This does after all prevent a conveyor belt being situated between the parts folded toward each other, which could result in irregularities at the end of the conveyor belt.

Another preferred embodiment provides the measure that the folding template comprises two strips, wherein the distance between the strips can be changed. It is hereby possible to change the width of the first article part, which is after all determined by the width of the folding template. It is then structurally attractive to place one of the slide tracks fixedly and to make the other movable.

This measure is embodied structurally in that the device comprises a spindle which extends substantially transversely of the direction of movement of the transport element and which is adapted to displace the strip on the first side of the folding template. The above stated elements are hereby connected to each other so that they can be moved together with a single drive.

In order to prevent the article part initially folded upward from being engaged by the disc which is adapted to exert a force on the article part to be folded thereafter, it is attractive that the first folding element comprises a part which extends above the first disc and the contour of which is adapted to the periphery of the first disc.

The device described thus far can fold an article of foldable material in lengthwise direction. There is usually a need for a device which can also make a fold in the transverse direction. A preferred embodiment of the invention provides for this purpose the measure that the transport element connects to a cross-folding device, and that the cross-folding device comprises a supply element for supplying the folded articles in substantially horizontal direction, a guide element placed under the discharge end of the supply element, wherein the guide element is adapted to guide parts of the folded articles released from the supply element, a discharge element for discharging by means of engagement folded articles coming from the supply element and situated partially on the guide element, an activating element for forcing the folded articles into engagement with the discharge element and a detection element for detecting the presence of a part of the folded sheet on the guide element and for activating the activating element when this presence is detected.

This preferred embodiment likewise relates to such a method, wherein the articles are carried from the transport element to a cross-folding device, and that in the cross-

folding device the parts of the folded articles released from the discharge end of the supply element are fed to a guide element and that, when reaching a position on the guide element, the articles are carried into engagement with a discharge element by activating an activating element and are subsequently discharged by the discharge element.

In order to reduce the number of moving parts of such a device as much as possible, it is attractive that the discharge element comprises two conveyor belts, and that the activating element comprises a blow nozzle leading to the point of engagement between the conveyor belts.

Making a single cross fold is not always sufficient. There is a need in many cases for a second cross fold. A further preferred embodiment of the invention therefore provides the measure that the device is provided with more than one such cross-folding devices.

The present invention will be elucidated hereinbelow with reference to the accompanying drawings, in which:

Figure 1 shows a schematic perspective view of a device according to the invention;

Figure 2 is a top view of the device shown in figure 1; Figures 3A-3F show cross-sectional views along the lines A-A, B-B, C-C, D-D, E-E and F-F in figure 2; and

Figure 4 shows a detailed longitudinal section view of the device.

The device shown in figure 1 comprises a frame which comprises two side plates 1 , 2 which are connected by various connecting elements, including a front connecting element 3. Placed in the frame is a horizontally extending folding template 4 over which a part of the article for folding is advanced. This folding template is rounded on the front side of the device. The folding template is formed by two strips 5, 6 arranged in a sub-frame 8. A conveyor belt 7 mounted in frame 1, 2 is arranged for driving the articles. Strip 5 has a fixed position in sub-frame 8. Using spindles 9, 10 the position of strip 6 inside sub-frame 8 and the position of sub-frame 8 can be adjusted so that both strips remain centred relative to conveyor belt 7.

For the purpose of guiding the articles for folding two folding elements 11 and 12 are arranged on either side of folding template 4. One of these folding elements is attached to side plate 1, while the other folding element is connected to sub-frame 8 so that it can be adjusted together with strip 5. These folding elements 11, 12 extend substantially vertically on the front side of the device but, more toward the interior of the device, they are oriented toward the centre of the belt for the purpose of guiding the articles for folding under conveyor belt 7. The folding elements comprise a first part which is folded three-dimensionally and ensures that the article is pre-folded and that the article only contacts the disc at a location where this latter has a sufficiently large movement component in the direction of forward movement. The second part of the plate forming the folding element forces the folded part of the article under the templates.

Reference is now made to figure 2 and the cross-sections according to figures 3A-F.

The invention provides a substantially horizontally disposed first disc 13 and a likewise substantially horizontally disposed second disc 14. The discs are each mounted on a shaft 15, 16 respectively. Both shafts are mounted in sub-frame 8 so that they can be displaced together with strip 5 and the folding element. Discs 13, 14 can be driven together by a motor which is not shown in the drawings and are driven by means of a toothed belt 18 with pulleys 19, 20 arranged on each of the shafts 15, 16 respectively.

The operation of this device will now be described. After switching on the drive of the discs, an article 25 for folding can be placed on templates 5, 6. The article 25 can then be placed by hand into engagement with conveyor belt 7, wherein conveyor belt 7 engages the article 25 for folding and transports it further in its direction of movement over template 4. In order to arrange the folds at the correct location in the article 25 for folding, use is preferably made of stops not shown in the drawing. A part of the article 25 for folding will herein be carried onto slide track 4 and a part of the article will hang downward on the left-hand side of slide track 4. This is the case when only a single fold has to be made. It is otherwise also possible for another part of article 25 to hang downward on the right-hand side. In this case the device will arrange two folds in article 25.

As already stated above, article 25 will be moved further by conveyor belt 7, wherein the driving takes place on that part of article 25 being advanced over slide track 4. The depending parts of article 25 are only carried along by the part of the article that is being advanced, whereby these parts, as a consequence of the friction encountered particularly due to folding elements 11, 12, will be pulled askew which, without further measures, would result in misoriented folds.

The invention however provides for the presence of discs 13, 14 which provide for driving of the depending parts of article 25 to an extent substantially corresponding with that of the conveyor belt. It is noted here that, instead of discs 13, 14, other types of drive element could be applied, such as belts. Discs 13, 14 are provided with bristles which extend in the radial direction of the disc and which engage the articles 25. The speed of the discs is chosen here such that the engaged articles are driven with a speed component in the direction of movement of conveyor belt 7 which is substantially equal to that of conveyor belt 7. The depending parts of the articles are hereby driven at the same speed as the non-depending parts, thus preventing misorientation. Discs 13, 14 also have the function of completing the process initiated by guide plates 11, 12 of folding the articles below conveyor belt 7. The discs are herein disposed such that they force the depending article parts into a horizontal position. In order to retain this horizontal folded position the discs 13, 14 connect to guides which carry the parts folded to a horizontal position. The movement is continued to a position beyond the end of template 4. Articles 25 are then folded in lengthwise direction.

In order to also fold the articles 25 in transverse direction, the folding device described up to this point, which is adapted to make folds in the lengthwise direction, connects to a cross-folding device. This cross-folding device is shown in figure 4. This cross- folding device comprises a conveyor belt 30 which connects to the first folding device and on which are supplied the articles folded in the lengthwise direction. Mounted under this conveyor belt is a guide plate 31 and placed above guide plate 31 and connecting thereto is a pair of conveyor belts 32, 33 which lead to a subsequent conveyor belt 34. Arranged connecting onto conveyor belt 34 is a guide plate 35 and a conveyor belt 36. Two nozzles 37 and 38 are also arranged, each connected to a source of compressed air.

The operation of this cross-folding device is as follows: the articles to be provided with a cross fold are supplied on conveyor belt 30. As soon as a part of the article is no longer supported by this conveyor belt it will drop downward, whereby it comes to lie on guide plate 31. This creates a fold in the article at the position of the end of conveyor belt 30. By moving the conveyor belt 30 further, the fold as it were displaces through the article. As soon as the bottom edge of the article has reached a predetermined position on guide plate 31, a detector is activated and nozzle 37 is switched on. The airflow generated hereby will impinge upon the article substantially at the position of the fold at the end of the conveyor belt. The airflow subsequently forces the article in the cross-folded state into a position between the engaging conveyor belts 32 and 33. The article is hereby provided with a single cross fold.

In many cases it is desirable to arrange a second fold in the article. For this purpose the single-folded article is fed from the position between conveyor belts 32 and 33 to a conveyor belt 34, in line with which a conveyor belt 36 is placed. As soon as the article has reached a predetermined position on conveyor belt 36, which is once again detected by a detector, nozzle 38 will be activated whereby at the position of the nozzle the article is forced downward between conveyor belts 34 and 36 onto guide plate 35. During this process a cross fold is once again arranged in the folded article. The thus folded article is discharged on guide plate 35.

It will be apparent that it is likewise possible to dispense with the arranging of a second cross fold, so that there only results an article provided with a single cross fold.