EP2801420B1

EP2801420B1 - Spring transfer device and spring transfer method

Info

Publication number: EP2801420B1
Application number: EP13167245.3A
Authority: EP
Inventors: Christoph Bischof; Luciano Amadori
Original assignee: Spuehl AG
Current assignee: Spuehl AG
Priority date: 2013-05-10
Filing date: 2013-05-10
Publication date: 2018-06-27
Anticipated expiration: 2033-05-10
Also published as: RU2638871C2; CN105188984A; PL2801420T3; EP2801420A1; CN105188984B; RU2015152806A; WO2014180586A1

Description

The present invention relates to a spring transfer device for the transfer of springs from a spring coiling machine.to a spring transport unit and a spring transfer method. In particular, the invention relates to such a spring transfer device that may be used in a machine for manufacturing spring core units, e.g., spring core units for mattresses.
Conventional machines for manufacturing spring core units comprise a spring coiling machine, a spring transport unit, and a spring core assembling machine as basic units. In the spring coiling machine, springs are coiled, knotted or bended and tempered. A transport star with a plurality of transport arms with grippers or hooks at each transport arm forwards the springs from the spring coiling machine to the transport unit. The transport unit may comprise a pair of spaced and parallel conveyor belts, the springs being inserted one after the other from the transport star between the conveyor belts so that the conveyor belts transport the springs as rows of aligned springs to the spring core assembling machine. In the spring core assembling machine, the rows of aligned springs are assembled to form the finished product, i.e., the corresponding spring core unit.
EP 2 316 783 A1 discloses a spring transfer device for the transfer of the springs from the transport star to the spring transport unit, in which the springs are pushed one after the other by means of pushers from the transport star between pairs of spaced rotary plates, the rotary plates allowing for a rotation of the corresponding spring held between the rotary plates around its longitudinal axis. This allows that the knots and/or ends of the springs are brought into a desired position on the conveyor belt, so that the knots and/or ends of the springs can be easily aligned individually for the assembly in the spring core assembling machine. For example, it is often desirable to arrange the springs in pairs with the knots or spring wire ends lying opposite to one another. Furthermore, the outer springs in a row of springs are usually rotated by 180 degrees about their longitudinal axes so that the free ends or the knots of these springs are aligned towards the respective adjacent spring in order to prevent that the ends of these outer springs penetrate through the mattress material.
The springs are transferred from the rotary plates to the conveyor belts by means of a further pusher, and the conveyor belts are guided along a 90° deflection such that the springs are brought from their horizontal orientation to a vertical orientation in which they are conveyed to the assembling machine.
A spring transfer device according to the preamble of claim 1 is known from WO 2005/077563 A1 .
It is the object of the present invention to provide a spring transfer device and a spring transfer method which require less space for the transfer of the springs from the spring coiling machine to the spring transport unit and which allow that the springs reach the spring transport unit already with the desired vertical orientation.
According to the invention, this object is achieved by a spring transfer device as defined in independent claim 1 and a spring transfer method as defined in independent claim 15. The dependent claims define preferred or advantageous embodiments of the invention.
According to an embodiment of the invention, a spring transfer device for transferring a spring from a spring coiling machine to a spring transport unit is provided, the spring device being configured such that it takes over the spring from the spring coiling machine at a first location and moves the spring to a second location for transfer to the spring transport unit. The spring device comprises a pivot mechanism for pivoting the spring, during the movement from the first location to the second location, from a first orientation, which the spring has at the first location, to a second orientation, which the spring has at the second location and which is substantially perpendicular to the first orientation.
According to a preferred embodiment, the first orientation is a horizontal orientation and the second orientation is a vertical orientation of the spring.
Furthermore, the spring transfer device may be configured such that it takes over the spring from one of a plurality of transport arms of a transport star, the transport star being rotated further by one transport arm per operating cycle and each transport arm of the transport star transporting one spring from the spring coiling machine to the spring transfer device. The pivot mechanism is configured such that it swings or pivots a base member from the first location, where the spring has the first orientation, to the second location, where the spring has the second orientation, and back from the second location to the first location during each operating cycle.
Furthermore, the pivot mechanism is preferably configured such that it moves the spring from the first location to the second location by a combined pivoting and translational movement, the first location being spaced from the second location along both a width direction and a height direction of the spring transfer device.
According to a preferred embodiment of the invention, the spring transfer device comprises a rotating mechanism for rotating the spring about its longitudinal axis while the spring is moved by the pivot mechanism from the first location to the second location and is pivoted from the first orientation to the second orientation. This allows that, once the pivoting by 90 degrees from the first orientation to the second orientation is completed and the respective spring has been moved from the first location to the second location, the knots of each spring are already in the correct position to undergo the spiral process in the assembling machine.
In the preferred embodiment, three movements are done simultaneously. First, each spring is transferred from the first location, where it is taken over from the spring coiling machine, to the second location, where is can be transferred to the spring transport unit. Second, the spring is simultaneously brought from its first orientation into its second orientation that allows the transport by the spring transport unit to the spring core assembling machine without need for any further re-orientation or alignment means. Third, the spring is rotated about its longitudinal axis so as to align the position of its ends and knots as desired. As these movements are done simultaneously, the spring transfer device requires less space than prior art devices.
Moreover, the spring transfer device of the invention allows for ergonomic operations as the springs come out of the spring transfer device at the correct height to be processed by the spring core assembling machine. Only very few adjustments are required if the spring height varies.
The pivot mechanism may comprise a pair of holding members, preferably in the form of rotary disks or rotary plates, which are spaced from one another such that they can take over the spring at the first location, hold it between the pair of holding members and rotate the spring about its longitudinal axis by rotation of the holding members. The holding members are preferably attached to the base member of the pivot mechanism so that they are moved and pivoted together with the base member.
According to the invention, the pivoting or swinging base member of the pivot mechanism is arranged movably along a fixed elongate shaft, the shaft having a curved groove where the base member engages the shaft so that the base member is pivoted from the first orientation to the second orientation when being moved along the shaft. Preferably, the curved groove is substantially S-shaped.
An eccentric drive mechanism may be provided for moving the base member along the shaft.
The present invention also provides a spring core manufacturing machine which comprises a spring coiling machine for providing coiled springs, a spring core assembling machine for manufacturing a spring core from a plurality of rows of coiled springs, a spring transport unit for transporting rows of aligned coiled springs to the spring core assembling machine, and a spring transfer device for taking over one spring from the spring coiling machine and transferring the spring to the spring transport unit during each operating cycle of the spring core manufacturing machine, the spring transfer device having the features of the above described spring transfer device.
According to a further embodiment of the invention, a method for transferring a spring from a spring coiling machine to a spring transport unit is provided, which comprises the steps of taking over the spring from the spring coiling machine at a first location, moving the spring to a second location for transfer to the spring transport unit, and pivoting the spring from a first orientation, which the spring has at the first location, to a second orientation, which the spring has at the second location and which is substantially perpendicular to the first orientation, during the movement step.
In the following, the invention will be described in detail with reference to preferred embodiments of the invention.

Fig. 1 shows a perspective view of a spring core manufacturing machine according to an embodiment of the invention.
Fig. 2 shows a side view of the spring core manufacturing machine embodying a spring transfer device according to an embodiment of the invention.
Fig. 3 shows an enlarged view of the spring transfer device during operation of the machine.
Fig. 4A shows a front view of the spring transfer device, and Fig. 4B shows a cross-sectional view along line A-A of Fig. 4A.
Fig. 5A shows a right side view of the spring transfer device shown in Figs. 4A and 4B, and Fig. 5B shows a cross-sectional view along line B-B of Fig. 5A.
Fig. 6A shows an enlarged right side view of central components of a pivoting mechanism of the spring transfer device shown in Figs. 4 and 5, and Fig. 6B shows a cross-sectional view along line C-C of Fig. 6A.
Fig. 7A and Fig. 7B show perspective views of the front and the back of the spring transfer device shown in Figs 4 - 6.
Fig. 8A shows a side view of a spring transfer device according to a further embodiment of the invention, and Fig. 8B shows a perspective view of the spring transfer device of Fig. 8A.

Fig. 1 shows a machine for the manufacture of spring core units according to an embodiment of the invention.
The machine shown in Fig. 1 comprises a wire swift 100 that supplies wire for the manufacture of coiled springs to a spring coiling machine 200. The spring coiling machine 200 processes the wire and manufactures coiled springs which are knotted at both ends. Furthermore, in the spring coiling machine, the coiled springs are tempered. The springs are forwarded from the spring coiling machine 200 to a spring transport unit 300 which transports rows of aligned springs to an assembling machine 400. In the assembling machine 400, the rows of aligned springs are assembled to form a finished product 500, i.e., a corresponding spring core unit.
Fig. 2 shows a side view of the machine shown in Fig. 1. As depicted in Fig. 2, a spring transfer device 50 is provided for the transfer of the springs from the spring coiling machine 200 to the spring transport unit 300. Furthermore, the machine comprises a transport star 10 having a plurality of transport arms to provide the springs from the spring coiling machine 200 to the spring transfer device 50.
The transport star is step-wise or cycle-wise rotated so that, during each cycle of the machine, one of the transport arms of the transport star 10 receives a new spring from the spring coiling machine 200 and one other transport arm forwards another spring to the spring transfer device 50. As will be described in the following in more detail, the spring transfer device preferably is configured such that, during each operating cycle of the machine, it takes over the spring at a first location from the respective transport arm of the transport star 10 and moves the spring to a second location where the spring is transferred to the spring transport unit 300. In particular, in the embodiment shown in Fig. 2, the spring transfer device 50 moves the spring received from the transport star 10 to the second location and simultaneously swings or pivots the spring from a horizontal first orientation to a vertical second orientation so that the spring reaches the spring transport unit 300 already in the desired vertical orientation. Furthermore, during the same cycle, the spring transfer device 50 swings back or returns to the first location so that it is ready to take over a spring from the next transport arm of the transport star 10 during the next operating cycle of the machine.
The spring transport unit 300 comprises a pair of parallel and spaced conveyor belts 41, 42 which extend in the longitudinal direction or width direction of the transport unit 300. When one of the springs has been moved to the second location, the spring is drawn in between the two conveyor belts 41, 42 so that a row of aligned springs 30 is conveyed by the spring transport unit 300 to the spring core assembling machine 400.
Fig. 3 is an enlarged view of the spring transfer device 50 shown in Fig. 2.
In particular, Fig. 3 shows the spring transfer device 50 in a state where it has already moved a spring 30 to the second location for transfer to the conveyor belts 41, 42 of the spring transport unit 300. Also shown in Fig. 3 is the transport star 10 with some of its transport arms 11 that are arranged spaced along the circumferential direction of the transport star. Each transport arm 11 has a gripper or hook 12 at its end portion and forwards a spring 30 from the spring coiling machine 200 to the spring transfer device 50 such that, when the spring transfer device takes over this spring 30 from the respective transport arm 11 at the first location, the spring 30 has a horizontal orientation. Thereafter, during the same operating cycle, the spring transfer device 50 moves the spring 30 to the second location shown in Fig. 3 and, thereby, pivots the spring 30 so that the spring has a vertical orientation at the second location and, thus, can be easily drawn in between the two conveyor belts 41, 42.
As will be explained in more detail below, in the preferred embodiment, the spring transfer device 50 is configured such that the movement of the spring 30 from the first location to the second location is a combined pivoting and translational movement. This means that the orientation of the spring at the second location is not only substantially perpendicular with respect to its orientation at the first location, but the second location is also spaced from the first location both in the width direction and in the height direction of the arrangement shown in Fig. 3.
Once the spring 30 has been transferred to the conveyor belts 41, 42, the spring transfer device 50 returns during the same cycle to the first location so as to receive, in the following cycle, another horizontally oriented spring from the next transport arm 11 of the transport star 10.
In the following, the functionality and structure of the spring transfer device 50 will be described in detail with respect to Figs. 4-7.
Fig. 4A shows a front view of the spring transfer device, and Fig. 4B shows a cross-sectional view along line A-A of Fig. 4A. Fig. 5A shows a right side view of the spring transfer device shown in Figs. 4A and 4B, and Fig. 5B shows a cross-sectional view along line B-B of Fig. 5A. Fig. 6A shows an enlarged side view of central components of a pivoting mechanism of the spring transfer device shown in Figs. 4 and 5 (from the right in Figs. 4 and 5), and Fig. 6B shows a cross-sectional view along line C-C of Fig. 6A. Finally, Fig. 7A and Fig. 7B show perspective views of the front and the back of the spring transfer device shown in Figs 4 - 6. Each of these figures shows the spring transfer device 50 at the second location for transfer to the spring transport unit 300.
The spring transfer device 50 comprises a pair of spaced holding members 70, 71 which are provided to receive a spring from one of the transport arms of the transport star at the first location and to hold the spring clamped between the holding members 70, 71 during the movement to the second location. When the holding members 70, 71 are at the first location, one of the transport arms of the transport star moves a spring between the two holding members 70, 71, and the holding members 70, 71 take over the spring from the respective transport arm.
In the preferred embodiment, both holding members 70, 71 are provided as rotary disks that are rotated during the movement of the spring transfer device 50 from the first location to the second location so as to rotate the spring, which is held between the holding members 70, 71, about its longitudinal axis to align the position of the knots and ends of the springs as needed. For this purpose, the holding members 70, 71 are mounted at a transmission shaft 74, e.g. a hexagonal transmission shaft, and are provided with cylindrical gears 72 that are in engagement with cylindrical gears 76 and 77, respectively. Each of the cylindrical gears 76 and 77 is supported by a gear shaft 78. The gears 72, 76 and 77 are driven by an electric motor 80, preferably a step motor, which is mounted at a motor support 79 adjacent a base 82 for the lower holding member 71.
The upper holding member 70 is supported by an arm 81 that is attached to a fixed column 73.
The base 82 for the lower holding member or rotary disk 71 is attached to a central base member 53 of a pivot mechanism that is provided for moving the holding members 70, 71 with the spring from the first location to the second location and, at the same time, pivot the holding members 70, 71 with the spring from the horizontal orientation at the first location to the vertical orientation at the second location.
As shown in Figs. 6A and 6B, the pivot mechanism also comprises left and right sliding rings 51, 52 that are arranged together with the central base member 53 movable along a fixed elongate shaft 54. The shaft 54 has a curved groove 55 which is in engagement with a projection 57 of the central base member 53. In a preferred embodiment, the curved groove 55 is S-shaped. The curvature of the groove 55 is such that, when the central base member 53 is moved in a horizontal direction along the shaft 54, the central base member 53 and the holding members 70, 71 attached thereto are pivoted by 90 degrees. This arrangement is attached to a connecting plate 59 that acts as a support for the pivot mechanism.
Figs. 4 - 7 show two eccentric drives. Reference numeral 63 designates a cam for an extractor device for drawing the spring, when the spring transfer device is at the second location, between the conveyor belts of the spring transport unit 300. The cam 63 is coupled with a lever 65 that is supported by a shaft fixing support 66.
The spring transport unit 300 is equipped with two carriers 43, 44 at each conveyor belt 41, 42 that are coupled by a vertical shaft 45 (see Fig. 3). The lower carrier 44 is coupled with a bearing 67 for the transmission of the movement. The bearing 67, fixed on a slider, is driven by the lever 65 and the cam 63 synchronously with the spring coiling machine 200. Each of these carriers 43, 44 is equipped with a pair of grippers 46, 47 that are preferably controlled by a solenoid. When the carriers 41, 42 move forward against the spring transfer device 50, the grippers 46, 47 are open. They close when the final position is reached, thereby drawing the respective spring 30 into the belt conveyor.
In addition, reference numeral 64 designates a cam of an eccentric drive for the pivot mechanism. The cam 64 is coupled to a lever 62 supported at a lever support 68. The lever 62 operates a pull-tie rod 61 shown in Fig. 5B (and also in Fig. 8).
The cams 63, 64 are both coupled to a cardan drive 60 of the main machine so that the operation of the cams 63, 64 is synchronized with the operation of the cardan drive 60 to ensure that the operating cycles of the cams 63, 64 correspond to the operating cycles of the other components of the machine.
When the spring transfer device is at the first location, i.e., when the holding members 70, 71 and the column 73 as well as the transmission shaft 74 are pivoted together with the central base member 53 to the horizontal orientation, and when the eccentric drive comprising the cam 64, the lever 62 and the pull-tie rod 61 is operated, the central base member 53 and the left and right sliding rings 51, 52 are moved along the shaft 54 in the width direction (i.e., to the right in Figs. 4 and 5). As the projection 57 of the central base member 53 is engaged with the curved groove 55 of the shaft 54, the base member 53 is at the same time pivoted or swung upwards so that, ultimately, it reaches together with the holding members 70, 71 the second location and the vertical orientation shown in Figs. 4 and 5 for transfer of the respective spring to the spring transport unit 300. Once the spring has been drawn into the spring transport unit 300, the cam 64 moves the central base member 53 and the sliding rings 51, 52 during the same operating cycle horizontally back along the shaft 54, thereby pivoting or swinging the base member 53 and the holding members 70, 71 back to the first location where they assume the horizontal orientation again.
As shown in Fig. 6B, the shaft 54 is provided with a second groove 56 that extends along a straight line in the longitudinal direction of the shaft 54 and is in engagement with a further projection 58 so that it serves as a guide for the horizontal movement of the above described arrangement along the shaft 54.
It should be noted that Fig. 6A shows a side view of the shaft 54, the central base member 53 and the right sliding ring 52 from the right side in Fig. 4A so that the orientation of the shaft 54 in the cross-sectional view of Fig. 6B is reversed with respect to the cross-sectional view shown in Fig. 5B.
The spring transfer device 50 also comprises a pair of support plates 86, 87 with curved recesses for the holding members or rotary disks 70, 71 when they are arranged with the horizontal orientation at the first location to receive a new spring from the transport star and a pair of support plates 84, 85 for the holding members 70, 71 when they are arranged with the vertical orientation at the second location for transfer of the respective spring to the spring transport unit 300. The support plates 84, 85 are mounted to a profile 83.
Fig. 8A and Fig. 8B show a spring transfer device according to another embodiment. In Figs. 8A and 8B, those parts which correspond to the parts shown in Figs. 4 - 7 are designated by the same reference numerals.
Figs. 8A and 8B shows the spring transfer device 50 in the horizontal position for receiving a spring from the transport star 10. As can be seen from Fig. 8A, the holding members/ rotary disks 70, 71 are arranged with the transmission shaft 74 and the column 73 such that they can receive between them a horizontally aligned spring from the transport star. Also shown are the gears 72 and 76, 77 and the step motor 80 for rotating the holding members 70, 71 during the pivoting movement of the pivot mechanism.
The functionality of the spring transfer device 50 shown in Figs. 8A and 8B is substantially the same as that of the spring transfer device discussed above with respect to Figs. 2 - 7, so that reference can be made to the above explanations in their entirety.

Claims

A spring transfer device (50) for transferring a spring (30) from a spring coiling machine (200) to a spring transport unit (300),
wherein the spring transfer device (50) is configured such that it takes over the spring (30) from the spring coiling machine (200) at a first location and moves the spring to a second location for transfer to the spring transport unit (300), and
wherein the spring transfer device (50) comprises a pivot mechanism (51-59) for pivoting the spring (30), during the movement from the first location to the second location, from a first orientation, which the spring (30) has at the first location, to a second orientation, which the spring (30) has at the second location and which is substantially perpendicular to the first orientation,
characterized in that
the pivot mechanism (51-59) comprises a base member (53) which is arranged movably along a fixed elongate shaft (54), the shaft (54) having a curved groove (55) where the base member (53) engages the shaft (54) so that the base member (53) is pivoted from the first orientation to the second orientation when being moved along the shaft (54).
The spring transfer device (50) according to claim 1,
characterized in that
the pivot mechanism (51-59) is configured such that it pivots the spring (30) from the first orientation being a horizontal orientation to the second orientation being a vertical orientation.
The spring transfer device (50) according to claim 1 or claim 2,
characterized in that
the spring transfer device (50) is configured such that it takes over the spring (30) at the first location from one of a plurality of transport arms (11) of a transport star (10), the transport star (10) being rotated further by one transport arm (11) per operating cycle and each transport arm (11) of the transport star (10) transporting one spring (30) from the spring coiling machine (200) to the spring transfer device (50), and
the pivot mechanism (51-59) is configured such that it moves from the first location, where the spring (30) has the first orientation, to the second location, where the spring (30) has the second orientation, and back from the second location to the first location during each operating cycle.
The spring transfer device (50) according to any one of claims 1-3,
characterized in that
the pivot mechanism (51-59) is configured such that it moves the spring (30) from the first location to the second location by a combined pivoting and translational movement, the first location being spaced from the second location along both a width direction and a height direction of the spring transfer device (50).
The spring transfer device (50) according to any one of claims 1-4,
characterized in that
the spring transfer device (50) comprises a rotating mechanism (70-87) for rotating the spring (30) about its longitudinal axis while the spring (30) is moved by the pivot mechanism (51-59) from the first location to the second location and is pivoted from the first orientation to the second orientation.
The spring transfer device (50) according to claim 5,
characterized in that
the spring transfer device (50) comprises a step motor (80) for driving the rotating mechanism.
The spring transfer device (50) according to any one of claims 1-6,
characterized in that
the spring transfer device (50) comprises a pair of holding members (70, 71) which are spaced from one another such that they can hold the spring (30) between the pair of holding members (70, 71) at the first location.
The spring transfer device (50) according to claim 7 and any one of claims 5-6,
characterized in that
the holding members (70, 71) are rotary disks being rotated by the rotating mechanism.
The spring transfer device (50) according to any one of claims 7-8,
characterized in that
the holding members (70, 71) are coupled to the base member (53) such that they are moved and pivoted together with the base member (53).
The spring transfer device (50) according to any one of claims 1-9,
characterized in that
the curved groove (55) is substantially S-shaped.
The spring transfer device (50) according to any one of claims 1-10,
characterized in that
the shaft (54) has a straight further groove (56) extending in a longitudinal direction of the shaft (54) for guiding the movement along the shaft (54).
The spring transfer device (50) according to any one of claims 1-11,
characterized in that
the spring transfer device (50) comprises a drive mechanism (61-62, 64) for moving the base member (53) along the shaft (54).
The spring transfer device (50) according to claim 12,
characterized in that
the drive mechanism comprises an eccentric drive (64) being coupled to the base member (53) via a lever (62).
A spring core manufacturing machine, comprising
a spring coiling machine (200) for providing coiled springs (30),
a spring core assembling machine (400) for manufacturing a spring core unit (500) from a plurality of the springs (30),
a spring transport unit (300) for transporting rows of the aligned springs (30) to the spring core assembling machine (400), and
the spring transfer device (50) according to any one of claims 1-13 for taking over one spring (30) from the spring coiling machine (200) and for transferring the spring (30) to the spring transport unit (300) during each operating cycle of the spring core manufacturing machine.
A method for transferring a spring (30) from a spring coiling machine (200) to a spring transport unit (300), comprising the steps
taking over the spring (30) from the spring coiling machine (200) at a first location and moving the spring (30) to a second location for transfer to the spring transport unit (300), and
pivoting the spring (30), during the movement from the first location to the second location, from a first orientation, which the spring (30) has at the first location, to a second orientation, which the spring (30) has at the second location and which is substantially perpendicular to the first orientation,
characterized in that
the step of pivoting the spring (30) uses a pivot mechanism (51-59) which comprises a base member (53) movably arranged along a fixed shaft (54), the shaft (54) having a curved groove (55) where the base member (53) engages the shaft (54) so that the base member (53) is pivoted from the first orientation to the second orientation when being moved along the shaft (54).
The method of claim 15,
characterized by the step of
using the spring transfer device (50) according to any one of claims 1-14 for the transfer of the spring (30) from the first location to the second location.