lifting device

Abstract

The invention relates to a lifting device (4) for lifting a workpiece carrier (1) from a conveyor (2) and / or for lowering a workpiece carrier (1) onto a conveyor (2), comprising a base body (7) with an element (5) which can be extended from the base body (7) and can be extended and retracted from the base body (7) in a predefined direction, comprising an actuating unit (9) for the targeted extension and retraction of the extendable element (5), wherein a holding body (15) is provided which carries the base body (7), wherein the base body (7) is guided so as to be displaceable relative to the holding body (15) between two end positions and the base body (7) can be fixed to the holding body (15) in an adjustment position between the two end positions, wherein the holding body (15) serves to fasten the lifting device (4).

Description

Technical field

[0001] The invention relates to a lifting device, in particular for lifting a workpiece carrier from a conveyor and / or for lowering a workpiece carrier onto a conveyor, in particular for use in automation technology for positioning a workpiece carrier. State of the art

[0002] In automation technology, it is known that workpiece carriers are moved by conveyors along a defined conveyor path. In this case, a workpiece or goods, etc. can be moved and transported by means of the workpiece carrier. It also happens that a workpiece transported on a workpiece carrier has to be processed at a processing station, whereby secure positioning of the workpiece is necessary for safe processing of the workpiece. In this case, the workpiece carrier is moved by the conveyor, whereby the movement of the workpiece carrier can be interrupted at a defined position by a stopper so that the workpiece carrier can be stopped at the defined position. However, the workpiece carrier is still resting on the conveyor, so safe processing cannot be guaranteed in this operating situation.Accordingly, lifting devices, also known as index cylinders, have become known. These can be used to lift the workpiece carrier from the conveyor to ensure smooth and secure positioning of the workpiece carrier. In this raised position, a workpiece positioned on the workpiece carrier can be machined, for example, so that it can then be lowered back onto the conveyor and transported further.

[0003] The lifting device has an extendable element for lifting the workpiece carrier, which in the lowered state is arranged below the workpiece carrier and at a distance from it, so that the workpiece carrier can move freely. In order for a workpiece carrier to be lifted, the workpiece carrier must be placed above the lifting device so that the extendable element of the lifting device can engage in a provided receptacle in the workpiece carrier when the extendable element is extended. Typically, several lifting devices are used to lift a workpiece carrier, which engage the receptacles arranged on the workpiece carrier at distributed positions, so that, for example, tipping of the workpiece carrier can be prevented.

[0004] Overall, it becomes clear that the positioning of the lifting device relative to the conveyor is of crucial importance, as otherwise a safe and correct lifting of the workpiece carrier from the conveyor cannot be achieved. To this end, the state of the art involves positioning the respective lifting device along the conveyor and screwing it into place. However, it becomes clear that the relative width of the conveyor varies along the path of the conveyor, so that the lateral position of the extendable element of the lifting device relative to the holder on the workpiece carrier can also fluctuate. This can lead to the extendable element not hitting the holder exactly and thus a safe lifting of the workpiece carrier cannot be achieved. Accordingly, the precise arrangement of the lifting device on the conveyor is of crucial importance.

[0005] The lifting device must be screwed to the conveyor in such a way that it is mounted in the correct position in the longitudinal direction of the conveyor, whereby the lateral fluctuations in the width of the conveyor and their laterally fluctuating distance must be taken into account. For example, if a lifting device is screwed precisely in the longitudinal direction of the conveyor, it may still be found that the lateral positioning of the lifting device with the extendable element is still incorrect, meaning that the lifting device must be dismantled, repositioned with washers in between, and screwed on again. This represents a considerable amount of work because the longitudinal positioning of the lifting device must be precisely maintained with each new screw connection in order not to disrupt the overall process.

[0006] DE 36 28 760 A1 discloses an assembly and processing system with linear transport of transport plates carrying workpieces, with conveyor elements for these transport plates and with elements for positioning the transport plates at predetermined work stations, wherein at least two height-adjustable positioning elements designed to engage in recesses in the transport plates and height-adjustable pressure elements for lifting the transport plates are provided at the work stations below the conveyor elements, and a stationary three-point counter bearing is arranged at each of the work stations above the transport plate, wherein the positioned transport plates can be pressed upwards against the three-point counter bearing by means of the pressure elements. Description of the invention, task, solution, advantages

[0007] It is the object of the invention to provide a lifting device which is improved over the prior art and allows easier assembly, in particular with regard to laterally exact positioning.

[0008] The problem is solved with the features of claim 1.

[0009] An embodiment of the invention relates to a lifting device for lifting a workpiece carrier from a conveyor and / or for lowering a workpiece carrier onto a conveyor, comprising a base body with an element which can be extended from the base body and which can be extended and retracted from the base body in a predefined direction, with an actuating unit for the targeted extension and retraction of the extendable element, wherein a holding body is provided which carries the base body, wherein the base body is guided so as to be displaceable relative to the holding body between two end positions and the base body can be fixed to the holding body in an adjustment position between the two end positions, wherein the holding body serves to fasten the lifting device.This allows the lateral position of the base body with the extendable element to be adjusted after the longitudinal position of the lifting device relative to the conveyor has been determined without having to abandon the longitudinal position. This significantly simplifies the precise positioning of the lifting device.

[0010] In one embodiment, it is also expedient if the holding body has a frame-shaped enclosure surrounding a recess, wherein the base body has a first base body region with reduced dimensions, which is received in the recess of the holding body and is displaceably guided in the recess of the holding body. As a result, the base body can be displaced within the recess of the holding body without the holding body itself having to be displaced. This facilitates the precise positioning of the lifting device, since the lifting device itself can be fixed in its longitudinal position by the holding body, wherein a subsequent positioning of the extendable element in the lateral direction can also be carried out by displacing the base body relative to the holding body.

[0011] According to a further aspect, it is also expedient if the base body has the first base body region with reduced dimensions and a second base body region, in particular with non-reduced dimensions, which adjoins the first base body region, wherein a clamping plate is also provided, which also adjoins the first base body region, such that the first base body region is arranged between the clamping plate and the second base body region. As a result, the holding body can be guided displaceably towards the base body and clamped between the base body and the clamping plate, so that the holding body can be easily and securely attached to the base body.

[0012] In a further embodiment, it is also expedient if the holding body receives the first base body region in its recess and the holding body with its frame-shaped enclosure is arranged between the clamping plate and the second base body region and can be clamped therebetween.

[0013] In a further embodiment, it is also expedient if the clamping plate can be screwed to the first base body region by means of screws, so that when the clamping plate is firmly screwed to the first base body region, the holding body is arranged and clamped between the clamping plate and the second base body region, and that when the clamping plate is loosely screwed to the first base body region, the holding body is displaceably arranged between the clamping plate and the second base body region. Thus, depending on the screwed state of the clamping plate to the first base body region, the base body can be firmly connected to the holding body or held displaceably.

[0014] It is particularly advantageous if an adjustment means is provided for adjusting the position of the first base body region within the recess of the holding means. This allows the position of the base body in the recess of the holding body to be precisely adjusted or changed. The adjustment means can also be a finely adjustable adjustment means, such as an adjusting screw, etc.

[0015] It is particularly advantageous if the adjusting means provides a threaded element, such as a threaded bolt or an adjusting screw, which is rotatably received in a thread, such as a threaded bore, of the holding body and thus longitudinally displaceable. An end region of the threaded element is positively and rotatably connected to the first base body region, so that upon rotation of the threaded element, the base body can be displaced within the holding body. The threaded element protrudes from the holding body and can thus be operated to displace the base body within the holding body.

[0016] It is also advantageous if the base body has a keyhole-shaped opening at the first base body portion for positively engaging the end portion of the threaded element into the base body. This allows for an easy-to-establish connection by engaging the threaded element, which also allows for secure force transmission for adjustment.

[0017] It is also expedient if the holding body has means for attaching the lifting device to a conveyor, such as at least one fastening rail and / or at least one screw hole for the passage of at least one fastening screw. Thus, the lifting device can be attached, for example, to a conveyor, such as a conveyor belt, a conveyor rail, etc., in order to lift a workpiece carrier moved by the conveyor, which has been stopped at a desired position.

[0018] It is also expedient if the extendable element, which can be extended and retracted from the base body in a predefined direction, is connected to a piston of the actuating unit for the targeted extension and retraction of the extendable element and the actuating unit has a piston-cylinder unit which guides the piston displaceably in a cylinder chamber, wherein the cylinder chamber can be connected to a pressure medium connection on both sides of the piston for pressurizing the cylinder chamber for displacing the piston in the cylinder chamber and for extending or retracting the extendable element. In this way, the extendable element can be extended and / or retracted using pressure medium, for example pneumatically, to lift the workpiece carrier, for example. This allows cost-effective actuation if a compressed air connection is already available.

[0019] Further advantageous embodiments are described by the following description of the figures and by the subclaims. Short description of the drawings

[0020] The invention will be explained in more detail below on the basis of at least one embodiment with reference to the drawing. It shows: Fig. 1 a schematic representation of a workpiece carrier which can be moved by means of conveyors and lifted by means of lifting devices, Fig. 2 a schematic, perspective view of an embodiment of a lifting device according to the invention, Fig. 3 a schematic side view of the embodiment of the lifting device according to the invention, Fig. 4 a schematic sectional view of the embodiment of the lifting device according to the invention, Fig. 5 a schematic representation of the embodiment of the lifting device according to the invention in a first setting, and Fig. 6 a schematic representation of the embodiment of the lifting device according to the invention in a second setting. Preferred embodiment of the invention

[0021] The Fig. 1 shows a workpiece carrier 1, which is moved by conveyor means 2. In the example shown, the workpiece carrier 1 is moved from right to left in the plane of the Fig. 1. The workpiece carrier 1 rests on the conveyor means 2 in certain areas and is thus moved in the conveying direction 3, corresponding to the x-direction.

[0022] The conveying means 2 are, for example, roller elements and / or belt elements, etc., for moving the workpiece carrier 1 in an application example of automation technology or material flow technology. The workpiece carrier 1 is, for example, a plate or a carriage, etc., which is moved by the conveying means 2.

[0023] If a workpiece on the workpiece carrier 1 is to be machined or otherwise treated, the workpiece carrier 1 must be lifted from the conveyor 2 to prevent vibrations, etc., from the conveyor 2 from being transferred to the workpiece carrier 1 and the workpiece to be machined. After machining, the workpiece carrier 1 can be lowered back onto the conveyor.

[0024] For this lifting and lowering process, lifting devices 4 according to the present invention are used. The invention relates to such a lifting device 4, in particular for lifting a workpiece carrier 1 from a conveyor 2 and / or for lowering a workpiece carrier 1 onto a conveyor 2, in particular for use in automation technology for positioning a workpiece carrier 1.

[0025] The lifting device 4 has an extendable element 5, which can engage with a provided receptacle 6 of the workpiece carrier when the extendable element 5 is extended. It is important that the extendable element 5 actually engages with the receptacle 6 in order to achieve secure positioning of the workpiece carrier 1 during lifting.

[0026] However, it can be seen that the distance A of the conveyor means 2 in the y-direction is provided with a certain tolerance, so that the distance B of the position of the holder 6 for the lifting device 4 on the workpiece carrier 1 from the edge of the conveyor means 2 is also subject to a tolerance.

[0027] In order to adapt the distance C of the extendable element 5 of the lifting device 4 from the edge of the conveyor means 2 to the distance B, the lifting device 4 serves according to the embodiment of the invention, as it is used for the Fig. 2 to 6 are described in detail.

[0028] The lifting device 4, also called index cylinder, according to the shown embodiment of the present invention, see the Fig. 2 to 6, serves to lift a workpiece carrier 1 from a conveyor 2 and / or to lower a workpiece carrier 1 onto a conveyor 2, as described above.

[0029] The lifting device 4 has a base body 7 with an element 5 which can be extended from the base body 7. The extendable element 5 is, for example, a cylindrical element, such as a plunger 8, as shown in the Fig. 2 to 6. The extendable element 5 can be extended from the base body 7 in a predefined direction, in particular vertically, and can be retracted into the base body 7 again.

[0030] To operate the extendable element 5, an actuating unit 9 is provided for the targeted extension and retraction of the extendable element 5. In the embodiment shown, see Fig. 4, the extendable element 5 is connected, for example screwed, to a piston 10 of the actuating unit 9 for the targeted extension and retraction of the extendable element 5.

[0031] The actuating unit 9 has a piston-cylinder unit 11 which guides the piston 10 in a cylinder chamber 12 in a displaceable manner, wherein on both sides of the piston 10 the cylinder chamber 12 can be connected to a pressure medium connection 13, 14 for pressurizing the cylinder chamber 12 for displacing the piston 10 in the cylinder chamber 12 and for extending or retracting the extendable element 5.

[0032] If the cylinder chamber 12 below the piston 10 is pressurized with a pressure medium, such as compressed air, and the cylinder chamber 12 above the piston 10 is vented, the extendable element 5 extends from the base body 7. This occurs by applying pressure medium to the pressure medium connection 14 and opening and venting the pressure medium connection 13.

[0033] If the cylinder chamber 12 above the piston 10 is pressurized with a pressure medium, such as compressed air or compressed air, and the cylinder chamber 12 below the piston 10 is vented, the extendable element 5 retracts into the base body 7. This is achieved by pressurizing the pressure medium connection 13 and opening and venting the pressure medium connection 14.

[0034] The control of pressurization and venting can be carried out valve-controlled, but this is not explicitly shown.

[0035] Furthermore, a holding body 15 is provided, which carries the base body 7.

[0036] The base body 7 is guided so as to be displaceable relative to the holding body 15 between two end positions, as shown in the Fig. 5 and Fig. 6 show. In Fig. 5 is also corresponding Fig. 4 the base body 7 is shown in a final position, wherein the base body 7 is in Fig. 6 is shown in the other end position relative to the holding body 15.

[0037] The base body 7 can be fixed in an adjustment position between the two end positions on the holding body 15.

[0038] The holding body 15 serves to secure the lifting device 4. For this purpose, the holding body 15 has means for securing the lifting device 4 to a conveyor 2, such as at least one fastening rail 17 and / or at least one screw hole 18 for the passage of at least one fastening screw. In the illustrated embodiment, two screw holes 18 are provided, which also extend through the fastening rail 17.

[0039] The holding body 15 is designed such that it has a frame-shaped enclosure 19 which surrounds a recess 20.

[0040] The base body 7 is divided into at least two base body regions 21, 22, wherein a first base body region 21 is provided with reduced dimensions and a second base body region 22, which adjoins the first base body region 21 with a shoulder 23 or the like.

[0041] The Fig. 4 shows that the first base body region 21 is received in the recess 20 of the holding body 15, wherein the first base body region 21 is also guided displaceably in the recess 20 of the holding body 15.

[0042] The base body 7 thus has the first base body region 21 with reduced dimensions and also the second base body region 22, which is not designed with reduced dimensions, in order to form the shoulder 23 as a type of guide surface for the holding body 15. The second base body region 22 thus adjoins the first base body region 21 via the shoulder 23.

[0043] Furthermore, a clamping plate 24 is provided, which also adjoins the first base body region 21. The clamping plate 24 adjoins the first base body region 21 on the opposite side of the second base body region 22. The first base body region 21 is arranged between the clamping plate 24 and the second base body region 22.

[0044] Advantageously, the base body 7 is formed in one piece with the first base body region 21 and with the second base body region 22 and the clamping plate 24 is formed as a separate component which can be connected, such as screwed, to the base body 7.

[0045] The holding body 15 receives the first base body region 21 in its recess 20. The holding body 15 with its frame-shaped enclosure 19 is arranged between the clamping plate 24 and the second base body region 22 and can be clamped therebetween, so that the holding body 15 can be securely connected to the base body 7.

[0046] The first base body portion 21 is slidably received in the recess 20, so that the first base body portion 21 is adjustable with the second base body portion 22 relative to the holding body 15. The Fig. 5 and Fig. 6 show that the base body 7 is adjustable relative to the holding body. In Fig. 5, the base body 7 is arranged so that it is aligned with the holding body 15. The distance X from the center of the extendable element 5 to the edge of the holding body 15 is smallest in this setting. Fig. 6, the base body 7 is arranged such that it protrudes from the holding body 15. The distance X from the center of the extendable element 5 to the edge of the holding body 15 is greatest in this setting. Accordingly, the base body 7 can be adjusted relative to the holding body 15 between these two settings in order to adjust the dimension X, whereby the dimension X also represents the distance from the center of the extendable element 5 to the conveyor 2.

[0047] The Fig. 2 shows that the clamping plate 24 can be screwed to the first base body region 21 by means of screws 25, so that when the clamping plate 24 is firmly screwed to the first base body region 21, the holding body 15 is arranged between the clamping plate 24 and the second base body region 22 and the holding body 15 is clamped accordingly. This fixes the holding body 15 relative to the base body 7 and the clamping plate 24. When the clamping plate 24 is loosened on the first base body region 21, the holding body 15 is released between the clamping plate 24 and the second base body region 22 and is thus arranged displaceably, see also Fig. 4.

[0048] For adjusting the position of the first base body region 21 relative to the holding body 15, an adjusting means 26 is provided, by means of which an adjustment of the position of the first base body region 21 within the recess 20 of the holding body 15 can be achieved.

[0049] According to Fig. 4, the adjusting means 26 is a threaded element, such as a threaded bolt, which is rotatably received in a thread 27 of a bore of the holding body 15 and thus longitudinally displaceable. The adjusting means 26, designed as a threaded element, can be changed in its axial position by rotation. An end region 28 of the adjusting means 26, designed as a threaded element, is positively and rotatably connected to the first base body region 21, so that upon rotation of the adjusting means 26, designed as a threaded element, the base body 7 is displaceable in the holding body 15.

[0050] Advantageously, the base body 7 has a keyhole-shaped opening 29 on the first base body region 21 for the positively engaging attachment of the end region 28 of the adjusting means 26, which is designed as a threaded element, into the base body 7. As a result, the adjusting means 26 can be rotated in the base body 7 so that it also displaces the base body 7 upon an axial displacement of the adjusting means 26. List of reference symbols 1 workpiece carrier 2 funding 3 Conveying direction 4 Lifting device 5 extendable element 6 Recording 7 basic bodies 8 plungers 9 Actuating unit 10 pistons 11 Piston-cylinder unit 12 Cylinder chamber 13 Pressure medium connection 14 Pressure medium connection 15 holding bodies 17 Mounting rail 18 screw hole 19 frame-shaped enclosure 20 recess 21 first basic body area 22 second body area 23 paragraph 24 clamping plate 25 screws 26 adjustment devices 27 threads 28 End area 29 keyhole-shaped opening

Claims

[1] Lifting device (4) for lifting a workpiece carrier (1) from a conveyor (2) and / or for lowering a workpiece carrier (1) onto a conveyor (2), with a base body (7) with an element (5) which can be extended from the base body (7) and can be extended and retracted from the base body (7) in a predefined direction, with an actuating unit (9) for the targeted extension and retraction of the extendable element (5), wherein a holding body (15) is provided which carries the base body (7), wherein the base body (7) is guided so as to be displaceable relative to the holding body (15) between two end positions and the base body (7) can be fixed to the holding body (15) in an adjustment position between the two end positions, wherein the holding body (15) serves to fasten the lifting device (4). [2] Lifting device (4) according to claim 1, characterized byin that the holding body (15) has a frame-shaped enclosure (19) which surrounds a recess (20), wherein the base body (7) has a first base body region (21), in particular with reduced dimensions, which is received in the recess (20) of the holding body (15) and is displaceably guided in the recess (20) of the holding body (15). [3] Lifting device (4) according to claim 2, characterized by in that the base body (7) has the first base body region (21) with reduced dimensions and a second base body region (22), in particular with non-reduced dimensions, which adjoins the first base body region (21), wherein a clamping plate (24) is also provided, which likewise adjoins the first base body region (21), such that the first base body region (21) is arranged between the clamping plate (24) and the second base body region (22). [4] Lifting device (4) according to claim 3, characterized by that the holding body (15) receives the first base body region (21) in its recess (20) and the holding body (15) with its frame-shaped enclosure (19) is arranged between the clamping plate (24) and the second base body region (22) and can be clamped therebetween. [5] Lifting device (4) according to claim 4, characterized by that the clamping plate (24) can be screwed to the first base body region (21) by means of screws (25), so that when the clamping plate (24) is firmly screwed to the first base body region (21), the holding body (15) is arranged and clamped between the clamping plate (24) and the second base body region (22) and that when the clamping plate (24) is loosely mounted on the first base body region (21), the holding body (15) is displaceably arranged between the clamping plate (24) and the second base body region (22). [6] Lifting device (4) according to one of the preceding claims 2 to 5, characterized bythat an adjusting means (26) is provided for adjusting the position of the first base body region (21) within the recess (20) of the holding body (15). [7] Lifting device (4) according to claim 6, characterized by that the adjusting means (26) provides a threaded element, such as a threaded bolt, which is rotatably and thus longitudinally displaceably received in a thread (27) of the holding body (15), wherein an end region (28) of the threaded element is positively and rotatably articulated to the first base body region, so that upon rotation of the threaded element the base body (7) is displaceable in the holding body (15). [8] Lifting device (4) according to claim 7, characterized by that the base body (7) has a keyhole-shaped opening (29) on the first base body region (21) for positively suspending the end region (28) of the threaded element in the base body (7). [9] Lifting device (4) according to one of the preceding claims, characterized by that the holding body (15) has means for fastening the lifting device (4) to a conveying means (2), such as at least one fastening rail (17) and / or at least one screw hole (18) for the passage of at least one fastening screw. [10] Lifting device (4) according to one of the preceding claims, characterized bythat the extendable element (5), which can be extended and retracted from the base body (7) in a predefined direction, is connected to a piston (10) of the actuating unit (9) for the targeted extension and retraction of the extendable element (5), and the actuating unit (9) has a piston-cylinder unit (11) which guides the piston (10) displaceably in a cylinder chamber (12), wherein on both sides of the piston (10) the cylinder chamber (12) can be connected to a pressure medium connection (13, 14) for pressurizing the cylinder chamber (12) for displacing the piston (10) in the cylinder chamber (12) and for extending or retracting the extendable element (5).

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