DE8813421U1 - Device for feeding laundry items to a mangle - Google Patents

Description

The invention relates to a device for feeding laundry items to a mangle or the like according to the preamble of claim 1.

10

Such a device is known from DE-PS 31 19 600. Here, the spreading and conveying device has two clamps into which the corners of the laundry item are clamped with a small distance between the clamps and by moving the clamps apart, the laundry item is spread out in a freely hanging downwards state. The transfer device then transfers the laundry item spread out in this way to a

Feed conveyor which then transports the laundry item to the mangle.

It has proven to be disadvantageous in this known device that, with larger items of laundry, a relatively high tension must be exerted on the upper edge of the same in order to avoid a sagging of the upper edge, particularly of larger items of laundry, which is disruptive when it is transferred to the feed conveyor or the mangle or the like. This leads to the two 10

When the item of laundry is spread out, clamps exert relatively large clamping stresses on the clamping points, which can lead to damage to the corner areas of the item of laundry that are gripped by the clamps.

In order to counteract the mentioned risk of damage to the laundry items by the clamps, appropriately gentle clamps have already been made known according to DE-PS 32 12 397, but these do not include

large clamping forces for clamping wide laundry items 20

This does not constitute an impairment of the same, at least if sufficiently high clamping forces are applied to reliably prevent a corner of the laundry from being pulled out of a clamp.

Based on this, the invention is based on the object of creating a device of the generic type, which enables sufficient spreading out of even large items of laundry in a reliable and yet gentle manner.

To solve this problem, the device according to the invention has the features of claim 1. By means of the additional clamp, preferably a middle clamp, the upper edge of the item of laundry to be spread out is also held in place in an intermediate position in addition to the corners.

This keeps the sag of the

upper edge of the laundry item is avoided or at least reduced even with large (wide) laundry items, without

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that - as in the state of the art - the (outer) clamps gripping the corners of the laundry must exert such a large tensile load on the upper edge of the laundry that damage to the corners at the

Pinch points are to be feared.
5

It is advisable to attach the additional clips to the upper edge of the laundry after attaching the outer clips and pre-spreading the

laundry item by partially moving the 10

outer brackets. This means that - as with the current

Technology - the laundry items are only clamped by hand into the usually manually operated outer clamps, while the middle clamp or other additional clamps mechanically hold the upper edge of the drawn-out 15

Since this gripping takes place in a pre-spread state of the laundry item, i.e. with the upper edge still hanging, the outer clamps do not exert any high tensile stresses on

the laundry item, which may cause impairments, in particular-20

especially at the terminal points.

It is also proposed to arrange a single central clamp in a fixed position in relation to the movement path of the outer clamps approximately in the middle of the feed conveyor. While the outer clamps can be moved to hang up a piece of laundry and to spread it out, the central clamp remains fixed in place where it is used for additional holding.

of the upper edge of the laundry item 30

ollen, that is, each piece of laundry is

to the middle clamp. This has the advantage that in (larger) devices with several pairs of outer clamps that can be alternatively loaded with a piece of laundry, all pairs of clamps work together with the same middle clamp.

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It is expedient for the middle clamp, which is stationary in terms of its position relative to the feed conveyor, to be movable in a plane transverse to the path of movement of the outer clamps or transverse to the plane of the item of laundry to be spread out, and preferably in an upright transverse plane. This allows the item of laundry to be moved unhindered with the outer clamp partially past the middle clamp into an approximately central position to the middle clamp and then the middle clamp to be inserted into the path of movement of the outer clamp.

move to grip the (still) sagging upper edge of the laundry item. For this purpose, in a particularly advantageous embodiment of the invention, the middle clamp is arranged on a support arm, which can be moved in a straight line across the plane of the laundry item to enter the path of movement of the outer clamps and can also be pivoted in a vertical plane to grip the sagging upper edge of the laundry item.

Another special feature of the invention relates to the design of the middle clamp and an actuating device for opening and closing it. Accordingly, the middle clamp has two clamp halves that can be moved in opposite directions around a common pivot axis, which in a preferred embodiment of the invention are designed as equally designed double levers, each with a clamp leg and an actuating leg. The two clamp halves are mounted on the common axis of rotation in a mirror image of each other, so that their actuating or clamping legs roughly cross. Due to this arrangement and design of the clamp halves, the clamping legs are moved towards or apart from each other by equally pivoting the actuating legs to close or open the middle clamp.

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According to an advantageous development of the invention, the opposite free ends of the actuating legs of the two clamp halves are connected to one another by at least one tension element (tension spring). Due to a special angled position of the free ends of the actuating legs to the clamp legs on the one hand and a corresponding relative position of the axis of rotation to the free ends of the actuating legs on the other hand, the tension element (or the tension elements) acts as an over-dead center tension element. For this purpose, both when the clamp legs are moved apart and when the clamp legs are moved together, the free ends of the actuating legs and the tension element(s) connecting them are located above or below the axis of rotation, whereby the clamp halves of the middle clamp are held alternatively in both a closed and an open position by the tension elements alone.

An embodiment of the device is explained in more detail below using the drawing. It shows:

Fig. 1 a vertical longitudinal section through the device with the clamps open,

Fig. 2 a section through the device according to

of Fig. t, but with the laundry item gripped by the clamps,

Fig. 3 is a schematic front view

the device when paired together

laundry hanging on clamps,

Fig. 4 is a view of the device according to the
Fig. 3 with pre-spread and through

three clamps gripped the piece of laundry,
36

Fig. 5 is a view of the device according to the
Pig. 3 and 4 at fully expanded
ted laundry item,

Fig. 6 is an enlarged rare view of the
middle bracket,

sees the one on a support arm arranged

Fig. 7 is an enlarged vertical section through the middle bracket,

Fig. 8 a top view of the middle bracket
of Fig. 7,

Fig. 9 a section IX-IX through the middle
Clamp according to Fig. 7 and

Fig.10

up to 15 schematic representations of various

Positions of the middle bracket to illustrate the functional sequence when grasping and

Releasing an upper edge of the laundry item.

The device shown here is used to feed spread out items of laundry 20 to a mangle not shown in the figures. The device is made up of a spreading and conveying device 21 for spreading out the items of laundry 20, a feed conveyor 22 and a transfer device 23. The latter transfers the spread out items of laundry 20 to the feed conveyor 22, which finally conveys the items of laundry 20 to the mangle.

The spreading and conveying device 21, the feed conveyor 22 and the transfer device 23 are mounted on a common machine frame 24 in a manner known per se in a functionally appropriate manner. The directions of movement of the feed conveyor 22 and the transfer device 23 are indicated by the arrows 25 and 26 in

1 and 2. Otherwise, the feed conveyor 22 and the transfer device 23 shown here are designed as in the known device according to DE-PS 31 19 600.

The spreading and conveying device 21 is provided in accordance with the invention with three clamps, namely two conventional outer clamps 27 and 28 and an additional middle clamp 29. Alternatively, in larger devices, several, in particular two pairs of outer clamps 27, 28, which alternately spread out one item of laundry 20 each, can be provided. In this case, all pairs of outer clamps 27, 28 are assigned only one single middle clamp 29.

The outer clamps 27, 28 can correspond in their design to the clamps of the device according to DE-PS 32 12 397.

The drive of the outer clamps 27, 28 can be in itself

As is known, this can be done both dragging in one direction and spreading in opposite directions. In the embodiment shown here, the outer clamps 27, 28 are dragged by a belt drive 30 associated with them. This

has a drive drum 31 and a deflection drum 32, around which a belt, namely a toothed belt 33, is guided. The belt drive 30 is driven by a preferably pole-changing electric motor 34, which is connected to the drive drum 31 via a chain drive 35.

Instead of the chain drive, other suitable drive elements can be arranged between the electric motor 34 and the drive drum 31. Instead of the electric motor 34, a suitable gear motor can also be used.

find use.
35

The outer clamps 27, 28 are assigned to the belt drive 30 via corresponding carriages 36, 37. In the direction of movement (arrow 38) of a lower run 39 of the toothed belt 33, the front carriage 36 is firmly connected to the toothed belt 33. In contrast, the carriage 37 behind it is not connected to the toothed belt 33 or is only connected with friction. The rear carriage 37 is therefore supported by rollers 40 connected to it on a guide rail 41 running parallel to the belt drive 30. In this way,

^1W by the belt drive 30 only a drive of the carriage 36 located at the front in the direction of movement (arrow 38), while the rear carriage 37 is freely movable, or braked by the upper run 42 moving in the opposite direction to the lower run 39, dragged along to the

Pre-spreading the laundry item 20.

As can also be seen particularly clearly from Fig. 4, a fixed stop 43 is assigned to the upper run 42 of the belt drive 30. This fixes the rear carriage 37 in an approximately central position of the spread out item of laundry 20 relative to the feed conveyor 22 and can also lead to a slight bending apart of the carriages 36, 37 for the complete spreading out of the item of laundry 20 or for slight tensioning.

serve the same.

Fig. 6 shows particularly clearly the mounting of the middle clamp 29 on a support arm 44. This is designed as a lever 46 that can be tilted around an approximately central pivot point 45. The lever 46 is mounted on the machine frame 24 in a fixed position with respect to the movement of the item of laundry 20 caused by the outer clamps 27, 28 via a pivot bearing 47 assigned to the pivot point 45. The middle clamp 29 is articulated via a clamp head 48 connected to it on the lever 46 of the support arm 44 by a pressure medium cylinder assigned to it, namely a pneumatic cylinder 49.

This is connected on the one hand with one end of its cylinder 50 in an articulated manner by a fork 51 to a free end 52 of the lever 46 and on the other hand with the front end of its piston rod 53 on the clamp head 48

the middle bracket 29. The front of the

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-' Cylinder 50 is located opposite the fork 51

the end area of the lever 46. Due to this assignment of the middle clamp 29 to the support arm 44, it can be moved back and forth by the pneumatic cylinder 49 on a straight path of movement transversely to the item of laundry 20.

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Furthermore, the pneumatic cylinder 49 can be pivoted about the pivot point 45 of the lever 46 together with the clamp head 48 of the middle clamp 29 attached thereto in an upright plane transverse to the plane of the spread

laundry item 20. The pivoting of the lever 46 takes place

, by another pressure cylinder, namely a

Pneumatic cylinder 54. This is connected on the one hand to its piston rod 55 with the piston rod 56 directed to the middle clamp 29.

if- connected to the opposite end of the lever 46, while at the other

20

on the one hand with the end of its cylinder 57 by a

another joint 58 is fixedly connected to a cross member 59 assigned to the machine frame 24 by a cantilever arm 60.

IS is tied.

'§ Fig. 7 to 9 show the formation of the middle

Clamp 29. This has two equally designed clamp halves 61, which are pivotable about a horizontal axis of rotation 62 on the underside of the

clamp head 48. Each clamp half 61 30
is designed as a two-armed lever, which has a

% central bearing sleeve 63 mounted on the bearing axis 62

&psgr; has a clearest "leg 64 and an opposite

horizontal actuating leg 65 is arranged si' ¹ . Jer

S Clarifier leg 64 and the operating leg 65 each

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Bracket halves 61 enclose an obtuse angle.

βgr; By 180° to each other (mirror-inverted) arrangement

g of the two identical clamp halves 61 on the rotation axis

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62 the clamp legs 64 and actuating legs 65 intersect, i.e. on one side of the axis of rotation 62 an actuating leg 65 of the other half of the clamp 61 is located above the clamp leg 64 of one half of the clamp

Bracket half 61.
5

The (obtuse) angle enclosed by the clamp leg 64 and the respective actuating leg 65 of each clamp half 61 is selected such that when the middle clamp 29 is opened as shown in Fig. 7, the clamp legs 64 of both clamp halves 61 are spaced apart in an approximately V-shape. In this position of the clamp legs 64, as shown in Fig. 7, there is an imaginary connecting line 66 between the free ends 67 of the actuating legs 65 below the rotation axis 62. The free ends 67 of the actuating legs 65 are connected by a tension member, which in the present embodiment is formed from two parallel tension springs 68. The tension springs 68 hold the actuating legs 65 together in the direction of movement towards one another, whereby the two clamp legs 64 of the middle clamp 29 are held apart in the opening direction, i.e. in a V-shape. In the closed position of the middle clamps 29, which is indicated in Fig. 7 by dotted lines, the clamp legs 64 of both clamp halves 61 lie together in an almost vertical position, for which both actuating legs 65 must be swung up at the same time. The free ends 67 of the actuating legs 65 then lie with the tension springs 68 connecting them above the axis of rotation 62, where

The tension springs 68 in turn pull the actuating legs 65 together to hold the clamp legs 64 together while clamping the corresponding middle area of the upper edge 85 of the laundry item 20.

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Due to the above-described design of the middle clamp 29, it is held both open and closed by the same tension elements, namely the tension springs 68, in that the special design and arrangement of the actuating legs 65 relative to the axis of rotation 62 means that the tension springs 68 act as so-called top dead center tension springs 68, in that when the clamp halves 61 pivot from the closed to the open position beyond their dead center in the plane of the axis of rotation 62, they are caught from one side to the other side of the axis of rotation 62. In order for the tension springs 68 to be able to move past the axis of rotation 62 unhindered, the actuating legs 65 are provided with hooks 69 protruding from the axis of rotation 62 to receive corresponding eyelets 70 at the ends of the tension springs 68, as shown in Fig. 9.

To close and open the middle clamp 29, i.e. to pivot the clamp halves 61 towards each other, an actuating device 71 is assigned to the clamp head 48. This has two push rods 72, each of which is connected in an articulated manner to a different actuating leg 65 by a corresponding connecting piece 73. The push rods 72 are each guided through a guide hole 74 through the clamp head 48 and are connected to one another at their upper ends by a horizontal bridge bracket 75. By moving the bridge bracket 75 up or down, the clamp halves 61 can be pivoted together about the axis of rotation 62 via the push rods 72.

Furthermore, the actuating device 71 for the upward movement of the bridge tab 75 and the resulting closing of the middle clamp 29 has a pressure cylinder arranged in the clamp head 48, namely a pneumatic cylinder 76, the piston 77 of which rests under the bridge tab 75.

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When the pneumatic cylinder 76 is vented, the bridge tab 75 is moved downwards to open the middle clamp 29 by a clamp opener that can be moved in a vertical direction and is only indicated by an actuating rod 78 in Fig. 7. It is expedient for the clamp opener to open both the middle clamp 29 and the two outer clamps 27, 28 at the same time.

Finally, in the present embodiment, a light barrier 79 is assigned to the clamp head 48. As can be seen from Figs. 7 and 9, a retaining tab 80 or 81 is attached to opposite sides of the clamp head 48, of which the retaining tab 80 has a photocell 82 pointing towards the retaining tab 81. In contrast, the side of the retaining tab 81 facing the retaining tab 80 has a reflector 83 opposite the photocell 82. The arrangement of the photocell 82 and the reflector 83 on the clamp head 48 is such that the light barrier 79 is located transversely below the axis of rotation 82 of the middle clamp 29, whereby the upper edge 85 of the item of laundry 20 to be gripped can enter the light beam of the light barrier 79 transversely without hindrance.

The following describes the functionality of the device and

in particular the middle bracket 29 will be explained with reference to Figs. 10 to 15.

As already known from DE-PS 31 19 600,

Next, the upper, opposite corners 84 of the laundry item 20 are manually clamped into the outer clamps 27, 28 as shown in Fig. 3. The laundry item 20 is then pre-spread out. This is shown in Fig. 4. In this state, the upper edge 85 of the laundry item 20 is only slightly stretched, so that the laundry item 20 is held between the two outer clamps 27, 28 due to its own weight.

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28 is still sagging. In this position of the item of laundry 20, in which it is already aligned centrally to the transfer device 23, the middle clamp 29 is placed approximately centrally on the upper edge 85 of the item of laundry 20.

If the laundry item 20 has the position shown in Fig. 4

has taken a forward-spread position, is

the middle bracket 29 with its support arm 44 in the

in the starting position shown in Fig. 10. In this 10

the lever 46 holds the still fully retracted

Pneumatic cylinder 49 in an approximately horizontal longitudinal position, whereby the clamping legs 64 of the middle clamp

29 are still pivoted apart, i.e. have an approximately V-shaped opening position. From this starting position, the piston rod 53, which holds the clamp head 48 with the middle clamp 29, is first extended completely horizontally from the pneumatic cylinder 49. As can be seen in Fig. 11,

after the middle

20

Clamp 29 the central axis of rotation 62 between the clamp halves 61 approximately above the upper edge 85 of the item of laundry 20. The lever 46 is then pivoted about its pivot point 45 by extending the vertical pneumatic cylinder 34, whereby the middle clamp 29 is lowered towards the upper edge 85 of the item of laundry 20. The extension stroke of the pneumatic cylinder 54, i.e. the downward pivoting of the middle clamp 29, is monitored by the light barrier 79 on the clamp head 48.

by entering the upper edge 85 of the laundry

stocks 20 into the light barrier 79 the downward swivel

movement of the pneumatic cylinder S4 is stopped. The middle clamp 29 is now in a position relative to the item of laundry 20, which is shown in Fig. 12.

This is followed by closing of the clamp legs 64

36

the middle bracket 29 by pressing the

Pneumatic cylinder 76 in the clamp head 48, which moves the actuating device 71 upwards. The middle clamp

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29 has then, according to the illustration in Fig. 13, firmly grasped the still sagging upper edge 85 of the item of laundry 20. The middle clamp 29 is then pivoted back by completely retracting the vertical pneumatic cylinder 54, whereby the pneumatic cylinder 49 for moving the middle clamp 29 has again reached its horizontal starting position. In this position, the middle clamp 29 is aligned horizontally with the two outer clamps 27, 28, so that the upper edge 85 of the item of laundry 20 is raised so far that it runs approximately straight as shown in Fig. 5. If necessary, the two outer clamps 27, 28 can then be moved further apart by the carriages 36, 37.

become.
15

The spread-out laundry item 20 is then transferred to the feed conveyor 22 by a horizontal movement of the transfer device 23, after which preferably both the middle clamp 29 and the

outer clamps 27, 28 are opened simultaneously by the clamp opener, and the middle clamp 29 reaches the position shown in Fig. 15. In order to return to the starting position according to Fig. 10, the opened middle clamp is then

29 is moved out of the area of the outer clamps 27, 28 by retracting the horizontal pneumatic cylinder 49.

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Applicant:

Herbert Kannegiesser GmbH + Go. Kannegiesserring

4973 Vlotho

-U 7 G-DB* ^#

List of reference symbols:

20 items of laundry

21 Spreading and conveying safety devices·*

22 feed conveyors

23 Transfer device

24 Machine frame

25 Arrow

26 Arrow

27 outer bracket

28 outer bracket

29 middle bracket

30 Belt drive

31 Drive drum

32 Deflection drum

33 Timing belt

34 Electric motor

35 Chain drive

36 carriages

37 carriages

38 Arrow

39 Lower strand

40 rollers

41 Guide rail

42 Upper run

43 stop

44 Support arm

45 Pivot point

46 levers

47 pivot bearings

48 Staple head

49 pneumatic cylinders

50 cylinders

51 Fork

52 free end

53 Piston rod

54 pneumatic cylinders

55 Piston rod

56 Joint

57 cylinders

58 Joint

59 Crossbeam

60 cantilever

61 Clamp half

62 Rotation axis

63 Bearing sleeve

64 staple legs

65 Actuating arm

66 imaginary connecting line

67 free end

68 Tension spring

69 hooks

70 eyelet

71 Actuating device

72 Push rod

73 Connector

74 Guide hole

75 Bridge plate

76 pneumatic cylinders

77 pistons

78 Operating rod (clamp opener)

79 Light barrier

-21-

80 Retaining tab 81 Retaining tab 82 Photocell 83 reflector 64 Corner 85 upper edge

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Claims (20)

Expectations 1. Device for feeding laundry items to a mangle or the like, with a spreading and conveying device for spreading the laundry items in a freely hanging downwards state, which has (outer) clamps that can be moved relative to one another, into which two corners of each laundry item can be clamped with a small distance between the (outer) clamps that can be moved away from one another, and with a transfer device for transferring the spread out hanging laundry item to a feed conveyor that conveys it towards the mangle, characterized by at least one further clamp (middle clamp 29) for gripping an upper Edge (85) of the laundry item (20) in the area between the outer clamps (27, 28). 2. Device according to claim 1, characterized in that the further clamp (middle clamp 29) or further clamps can be brought into engagement with the (still sagging) upper edge (85) of the item of laundry (20) after the outer clamps (27, 28) have been attached and before the item of laundry (20) has been completely spread out. 3. Device according to claim 1 or 2, characterized in that a single central clamp* (29) is arranged stationary with respect to the outer clamps (27, 28) approximately centrally to the feed conveyor (22). 4. Device according to claim 2 or 3, characterized in that the middle clamp (29) is movable transversely to the plane of the spread-out item of laundry (20), preferably in an upright transverse plane of the item of laundry (20) for grasping the upper edge (85) of the item of laundry (20) hanging between the outer clamps (27, 28) and for lifting the same. 5. Device according to claim 4, characterized in that the middle clamp (29) is arranged on a support arm (44) which can be moved back and forth in a straight line transversely to the spread-out item of laundry (20) and/or can be pivoted in a vertical plane. 6. Device according to claim 5, characterized in net that the support arm (44) has a pressure cylinder (pneumatic cylinder 49), to whose piston rod (S3) the middle clamp (29) is attached. 7. Device according to claim 5 or 6, characterized in that the support arm (44) has a lever (46) which can be pivoted about a stationary pivot bearing (47) and on which the fi provided with the middle clamp (29) Pressure cylinder (pneumatic cylinder 49) attached is. 8. Device according to claim 7, characterized in that the pivotable lever (46) can be pivoted by a further pressure medium cylinder (pneumatic cylinder 54). 9. Device according to one or more of claims 3 to 8, characterized in that the middle clamp (29) has two clamp halves (61) of the same design that can be moved in opposite directions about a common (central) axis of rotation (62). 10. Device according to claim 9, characterized in that the clamp halves (61) are designed as two-armed levers each having a clamp leg (64) for gripping the upper edge (85) of a respective item of laundry (20) and an actuating leg (65) which point at an obtuse angle to opposite sides of the rotation axis (62) and are connected to one another by a bearing sleeve (63) arranged (centrally) on the rotation axis (62). 11. Device according to claim 9 or 10, characterized characterized in that the clamp halves (61) are arranged with opposite set relative positions on the axis of rotation (62) in such a way that both when the middle clamp (29) is open and when it is closed, an (imaginary) connecting line (66) between the opposite free ends (67) of the actuating legs (65) on opposite sides of the axis of rotation (62) are located below or above the same. 4'* 12. Device according to one or more of claims 9 to 11, characterized in that the opposite free ends (67) of the actuating legs (65) are connected to one another by at least one over-dead-center tension member, in particular two over-dead-center tension springs (68). 13. Device according to one or more of claims 9 to 12, characterized in that the actuating legs (65) of both clamp halves (61) of the middle clamp (29) can be equally pivoted relative to the axis of rotation (62) by at least one actuating device (71) for opening and/or closing the clamp legs (64) connected to the actuating legs (65). 14. Device according to claim 13, characterized in that the actuating device (71) has two actuating legs each with a free end (67) (65) has articulated connecting rods (72) which are connected to one another by a bridge plate (75) for joint actuation. 15. Device according to claim 13 or 14, characterized in that the actuating device (71) can be moved up and/or down by at least one pressure medium cylinder (pneumatic cylinder 76). 16. Device according to claim 14, characterized in that the pressure cylinder is one of the A single-acting pneumatic cylinder (76) associated with the bridge bracket (75) is designed to move the actuating device (71) in the closing direction of the clamp legs (64). · t Φ · ■ 1 · I • · &igr;
• · · at« 17. Device according to one or more of claims 14 to 16, characterized in that the actuating device (71) is assigned, in addition to the pneumatic cylinder (76), a clamp opener (actuating rod 78) for opening the clamp legs (64) and for retracting the pneumatic cylinder (76). 18. Device according to claim 17, characterized in that the clamp opener is designed both for opening the clamp legs (64) of the middle clamp (29) and for (simultaneous) opening of the two outer brackets (27, 28) is trained. 19. Device according to one or more of claims 9 to 18, characterized in that the middle clamp (29) is assigned at least one light barrier (79) for controlling the clamping processes of the middle clamp (29), preferably for limiting the downward pivoting movement of the middle clamp (29) holding support arm (44) depending on the Relative position of the upper edge (85) of the laundry item (20) to the clamp legs (64) and to close the clamp legs (64). 20. Device according to claim 19, characterized in that the extension stroke of the vertical pneumatic cylinder (54) on the support arm (44) and of the pneumatic cylinder (76) for closing the clamp legs (64) of the middle clamp (29) can be controlled by the light barrier (79).