Welded Actuating Cylinder Assembly and Method for Manufacturing a Welded Actuating Cylinder Assembly

Abstract

The present invention relates to a welded actuating cylinder assembly having an actuating cylinder component 1, an attachment part 2, and a weld line 3, the weld line 3 being designed as a stepped hybrid weld line having a lower weld line zone 4 and an upper weld line zone 5. In the lower weld line zone 4, the actuating cylinder component 1 has a lower actuating cylinder component weld line surface 4.1, the attachment part 2 has a lower attachment part weld line surface 4.2, the lower weld line surfaces 4.1, 4.2 have a butt joint 4.3, and the lower weld line zone 4 is formed as a laser weld line. In the upper weld line zone 5, the actuating cylinder component 1 has an upper actuating cylinder component weld line surface 5.1, the attachment part 2 has an upper attachment part weld line surface 5.2, the upper weld line surfaces 5.1, 5.2 have a surface separation 5.3, and the upper weld line zone 5 is formed as a laser-hybrid weld line and has a filling of a weld filler 5.6 in an upper weld line space 5.5 formed by the surface separation 5.3. The present invention further relates to a method for manufacturing such a welded actuating cylinder assembly.

Description

Technical Field

[0001] The present invention relates to a welded actuator cylinder assembly and a method for manufacturing such an actuator cylinder assembly for a hydraulic actuator cylinder having a particularly high actuating force.

Background Art

[0002] It is known from the prior art to provide a hydraulic actuator cylinder with an attachment part for transmitting the actuating force generated by the actuator cylinder to a device to be actuated. Such an attachment part may in particular be a so-called rod eye.

[0003] Furthermore, it is known from the state of the art to weld to such an attachment part. In larger hydraulic cylinders, a very large force has to be absorbed here via the welded connection as intended, so that, for example, a weld seam manufactured as a MAG weld seam has to have a large weld seam area and thus a large weld seam depth.

[0004] The disadvantage of this design is, on the one hand, the high heat input required, which results in the risk of scaling in the actuator cylinder, thermal deformation or damage to components with lower resistance to thermal stress, such as seals or guides. Furthermore, the high consumption of welding wire and energy can be observed as a further disadvantage.

[0005] It is also known from the prior art to produce laser-welded joints where a very high laser power has to be used for the required weld depth, such that laser welding is disadvantageously very expensive and uneconomical.

[0006] The object of the invention is to provide a welded actuating cylinder assembly that can withstand very high loads and can be manufactured in an economical form that saves resources. Furthermore, the object of the invention is to provide a reliable and at the same time economical method for manufacturing such an actuating cylinder assembly.

[0007] With regard to the actuating cylinder assembly, the object is solved by the features claimed in claim 1, and with regard to the manufacturing process, by the features claimed in claim 5. Preferred further embodiments result from the respective dependent claims.

[0008] The basic components of the welded actuating cylinder assembly according to the invention are the actuating cylinder component, the attachment part and the weld line.

[0009] The actuating cylinder component is designed in a known manner as a piston rod or a closure part. For the purposes of the present invention, the actuating cylinder is understood to be a linear pressure flow consumption device in which a pressure medium acts on the piston surface, thereby providing an actuating force which can be a thrust or a pressure. Preferably, the actuating cylinder is a hydraulic actuating cylinder. The actuating cylinder can be designed, for example, as a differential actuating cylinder, a pull cylinder, a double-rod cylinder or a plunger cylinder.

[0010] The actuating cylinder component is the component of the actuating cylinder from which the actuating force is taken. In particular, this can be a closure part such as a bottom closure part. Furthermore, this can be a piston unit, in particular a piston rod, and the outer section of the plunger piston is also understood to be a piston rod.

[0011] The attachment part is a coupling module designed to be coupled to a device actuated to transmit force. When the actuating cylinder is used as intended, the coupling module is connected to the device to be actuated, usually in the form of a hinged connection, and for this purpose, the coupling module is designed as a coupling bearing, also called a rod eye or joint head. However, the coupling module can also be designed in different forms.

[0012] Hereinafter, the actuating cylinder component and the attachment part are also collectively called coupling partners.

[0013] Furthermore, the welded actuating cylinder assembly according to the invention has a weld line connecting the actuating cylinder component and the attachment part in the form of a positive substance.

[0014] This weld line is configured in a special form according to the invention and is formed as a step-by-step hybrid weld line manufactured in multiple steps.

[0015] For this design, the weld line has a lower weld line zone and an upper weld line zone. The position indication of the lower weld line and the upper weld line zone is understood independently of the position in space. Regarding the weld line depth, the lower weld line zone refers to a section facing in the direction opposite to the direction of attack of the component surface and the welding material, and the upper weld line zone refers to a section of the weld depth that is connected to the component surface, covers the lower weld line zone, and faces in the direction of attack of the welding material.

[0016] In the lower weld line zone, the actuating cylinder component has a lower actuating cylinder component weld line surface, and the attachment part has a lower attachment part weld line surface. Hereinafter, the lower actuating cylinder component weld line surface and the lower attachment part weld line surface are also called the lower weld line surface in a summarized form.

[0017] According to the present invention, the lower weld line surface has butt joints for each other joined in the form of a positive substance by a laser weld line. The laser weld lines are in the same plane, formed without gaps, and the welding is performed without welding a filler metal.

[0018] In the upper weld line zone, the actuating cylinder component and the attachment part also have weld line surfaces of the same shape at a predetermined distance from each other, and the space formed therebetween is called a weld line space. With this arrangement, the laser beam can pass through the laser weld line zone, thereby enabling laser welding in the lower weld line zone.

[0019] In this case, the actuating cylinder component has an upper actuating cylinder component weld line surface, and the attachment part has an upper attachment part weld line surface. Hereinafter, the upper actuating cylinder component weld line surface and the upper attachment part weld line surface are also collectively called the upper weld line surface. The lower and upper weld line surfaces are also collectively called the seam surface.

[0020] The upper weld line surfaces have a separation (distance) from each other. This means that the upper weld line surfaces are arranged in a substantially plane-parallel and spaced-apart form. The space thus formed between the upper weld line surfaces is called the upper weld line space. The upper weld line space is arranged to provide a free cross-section for the laser beam for the formation of the laser weld line in the lower weld line zone.

[0021] The upper weld line zone is formed as a laser-hybrid weld line under these design conditions and represents the basic part of the solution means according to the present invention. This is because the laser beam here preferably simultaneously accepts a welding electrode having a thickness of about 0.8 mm. Thereby, the upper weld line zone has a filling of the welding filler material, and the welding filler material fills the upper weld line space, thereby indirectly joining the upper weld line surfaces to each other in the form of a positive substance. The laser-hybrid weld line of the upper weld line zone is provided as a so-called I-weld line, which has a greater width than the laser weld line of the lower weld line zone according to the present invention.

[0022] Therefore, the upper weld line space advantageously simultaneously satisfies two functions that are essential for the solution means according to the present invention. This enables unobstructed access of the laser beam to the lower weld line zone. This provides the space required for receiving the welding filler material.

[0023] The welding filler material is preferably the material of a welding wire. The welding means of the upper weld line zone is also a laser beam. In this case, the laser beam in the upper weld line zone is applied following the laser beam in the lower weld line zone. Preferably, this is the same laser beam that is applied following the lower weld line zone and now impinges on the welding filler material in the upper weld line space. This can be realized in a particularly advantageous form for a rotationally symmetric welding partner. This is because the lower and upper weld lines can be formed continuously. The lower weld line is formed in the first rotation, the welding filler material is melted in the second rotation, and at the same time, the free space between the relevant welding partners is filled in the upper weld line space.

[0024] The bond provided by the present invention can also be called a laser-laser hybrid bond or a hybrid weld produced step by step. This has the following advantages in particular.

[0025] The butt joint in the lower weld line zone achieves particularly accurate positioning. This is because this weld line surface holds the welding partner in place without distortion during the immediately subsequent cooling process. A further advantage is the increased energy efficiency. This is because the solidification heat released from the lower weld line zone serves as preheating for the upper weld line zone. Furthermore, the separation of the total weld line into two weld line zones enables the application of a lower laser power, thereby allowing the use of a lower power laser welding system, which is very publicly effective with respect to investment costs and is advantageous from a manufacturing perspective. The application of laser-hybrid welding bonds enables the use of all known laser beam generation techniques such as YAG lasers and CO2 lasers and is not restricted to a specific type of laser generation. Another advantage from a technical perspective is the high processing speed at which a seam can be formed, which means that no expensive and time-consuming processing such as friction welding or pre-existing forgings is required at all. Finally, the quality of the weld joint is improved by the reduction of heat in the welding process, and scaling can be completely eliminated. As a result of this heat reduction, sensitive elements of the operating cylinder are protected.

[0026] In addition, the following applies in detail. In particular, a high-quality bond is provided. The butt joints in the lower weld line zone enable a particularly accurate positioning of the mating parts relative to each other. This exact positional relationship is reliably maintained during and after the welding process. Initially, a very low energy input per unit length is required in the lower weld line zone, and as a result, a surprising solution for minimizing thermal deformation has been discovered. This possible low energy input per unit length is based on laser welding technology on the one hand and on the reduction of the total weld line depth from the first to the lower weld line zone depth on the other hand. In addition, the energy input per unit length has a direct effect only in the lower weld line zone, so that the initially still cold material body in the area of the upper weld line zone supports the material body in the lower weld line zone and additionally counteracts its thermal deformation. In this regard, the formation of the upper weld line space also has the advantage of providing direct access to the laser beam to the lower weld line zone without additional effort.

[0027] Furthermore, the laser beam forms only a very narrow melt zone in the lower weld line zone, and correspondingly, a small heat energy input is required. This can be removed very quickly from the lower weld line surface into the material of the mating part, whereby solidification occurs quickly in the lower weld line zone. This means that when a longer cooling and solidification phase begins in the upper weld line zone due to a wider weld line and a higher heat input, the mating part is already fixed in place in the form of a positive substance, thereby counteracting the thermal displacement caused by the upper weld line zone.

[0028] Another advantage is the increased energy efficiency. The heat of solidification released in the lower weld line zone due to the solidification of the molten zone is dissipated into the material of the joining partner, providing residual heat for the weld line in the upper weld line zone, thereby reducing the energy input per unit length applied there by this amount. This has the particular advantage that the upper weld line zone is heated from below, whereby the subsequent rapid melting and heat homogenization of the upper weld line zone is achieved by the heat input of the laser beam during the second application from above.

[0029] Furthermore, it is advantageous from a technical point of view that both the lower laser weld line and the upper laser-hybrid weld line require a lower laser power than is required for laser welding of the entire weld line. Thus, a low-cost laser welding system with a lower power of about 5 - 10 KW can also be used to provide a welded operating cylinder assembly according to the invention for the manufacture of intermediate-sized hydraulic operating cylinder assemblies, significantly reducing the investment costs.

[0030] In addition, welding filler materials such as welding wire are only required for the upper weld line zone, so that materials and costs can be saved here.

[0031] Advantageously, the weld line can be formed in the vertical direction and at a predetermined angle.

[0032] Finally, by reducing the heating of the operating cylinder components, the quality is enhanced by avoiding scaling or damage to heat-sensitive elements.

[0033] According to claim 2 and another aspect of the invention, the actuating cylinder component is a cylinder tube, and the attachment part is a closure part or a further closure part. This one can be a closure part designed as a lower closure part in particular, welded to the coupling module according to the invention, or it can be another closure part not welded to the coupling module according to the invention. In particular, this can be a guide closure part. The closure part or further closure part in the sense of this further aspect of the invention is hereinafter abbreviated as the closure part.

[0034] Thus, the weld line according to this further aspect of the invention joins the cylinder tube to the closure part. In this design, the upper weld line zone is formed as an outer ring surface, and the lower weld line zone is formed as an inner ring surface. Also, the content of the description regarding the weld line of the welded joint between the piston rod or the closure part and the coupling module is applicable in a corresponding manner to the weld line of the welded joint between the cylinder tube and the closure part.

[0035] This aspect of the invention is particularly advantageous in the case of the welded joint according to the invention in heavy hydraulic cylinders. A heavy hydraulic cylinder is understood to be a hydraulic cylinder having a cylinder tube wall pressure of 10 mm or more, preferably 15 mm or more. Here, the preferred inner diameter of the cylinder tube is 100 mm or more, preferably 150 mm or more.

[0036] Manufacturing advantages, in particular, savings in costly welding filler materials, reduction of costs for the laser, and improvement of accuracy are quite important for heavy hydraulic cylinders.

[0037] According to a further advantageous development, the welded actuator cylinder assembly is characterized in that the lower weld line zone surface and the upper weld line zone surface together form the total weld line zone surface, and the surface ratio of the lower weld line zone surface to the total weld line zone surface is 15% to 40%. In a particularly preferred design, this surface ratio is 20% to 30%. It has been experimentally proven that at this ratio, the weld line can be formed extremely accurately and without distortion. Rapid solidification of the molten zone in the lower weld line zone is achieved.

[0038] Particularly in the case of the welded joint on the piston rod, the weld line surface has a rotationally symmetric geometry. When fully welded, the lower weld line zone of the rotationally symmetric part is the inner circular surface, and the upper weld line zone is the ring surface that radially surrounds the lower weld line zone. The inner circular surface of the lower weld line zone and the outer ring surface of the upper weld line zone together form the total circular surface, and this total circular surface forms the total weld line zone surface. Thereby, both surfaces form the total weld line. According to this further development, the surface ratio of the inner circular surface to the total circular surface is 15% to 40%, and in a particularly preferred design, it is 20% to 30%. It is an advantage that the two zones to be welded can be welded in only one clamping by two consecutive rotations.

[0039] According to a further advantageous development, the welded actuator cylinder assembly is characterized in that the surface separation in the upper weld line zone is 0.5 mm to 2.0 mm. In a particularly preferred design, the surface separation is 1.0 mm to 1.5 mm.

[0040] On the one hand, this surface separation advantageously allows good penetration of the laser beam into the lower weld line zone. On the other hand, it has been found that it also allows, in particular, low consumption of welding filler materials such as welding wire, and a relatively low energy input per unit length in the upper weld line zone together with reliable welding in the upper weld line zone.

[0041] According to a further advantageous development, the welded actuating cylinder assembly is characterized in that the lower weld line zone surface is formed as an inner circular surface or an inner ring surface, and the upper weld line zone surface is formed as an outer ring surface that radially surrounds the lower weld line zone surface. Both partial surfaces together form the total weld line zone surface, and thus the total weld line zone surface can be either a total circular surface or a total ring surface.

[0042] This further development is advantageous in both respects in that the heat dissipation after the formation of the laser weld line in the lower weld line zone is lower towards the bottom than towards the top due to the radial geometry. This fact also improves the residual heat in the upper weld line zone. At the same time, this further development is advantageous from a technical point of view because the lower weld line zone and the upper weld line zone can be successively realized in one clamping by two successive rotations of the pre-positioned joining partners under the laser beam.

[0043] According to another aspect of the invention, a method for manufacturing a welded actuating cylinder assembly is provided, wherein the actuating cylinder component is designed as a piston rod or a closure part, and the attachment part is designed as a coupling module. The coupling module is designed to be coupled to a device that is actuated for force transmission.

[0044] The method includes the following process steps: a) providing the actuating cylinder component and the attachment part; and b) manufacturing the weld line surfaces to be connected, i.e., manufacturing the lower actuating cylinder component weld line surface and the lower attachment part weld line surface, as well as the upper actuating cylinder component weld line surface and the upper attachment part weld line surface, wherein at least one of the upper weld line surfaces is set back with respect to the respective lower weld line surface. c) Positioning the actuating cylinder component and the attachment part to form a pre-assembly by manufacturing a butt joint on the lower weld line surface and creating a surface separation on the upper weld line surface; d) Laser welding the lower weld line surface by a laser beam by manufacturing a laser weld line in the lower weld line zone; e) Laser-hybrid welding the upper weld line surface by supplying a laser beam and a welding filler material, melting the welding filler material by the same laser beam, and filling the upper weld line space between the upper weld line surfaces.

[0045] The description content for the welded actuating cylinder assembly and the definitions of the terms used therein also apply, in corresponding form, to the method for their manufacture.

[0046] In process step a), the actuating cylinder component and the attachment part are provided. The manufacture of these two joining parts is carried out in a manner known per se.

[0047] In process step b), a lower actuating cylinder component weld line surface, a lower attachment part weld line surface, an upper actuating cylinder component weld line surface, and an upper attachment part weld line surface are formed, and at least one of the upper weld line surfaces is set back relative to the respective lower weld line surface.

[0048] Since the seam surfaces are usually rotationally symmetric component sections, they are preferably manufactured by turning or milling. In particular, the lower weld line surface preferably has a completely flat design. In the case of a symmetric design, the setback of the upper weld line surface is half of the desired surface separation later. However, an asymmetric distribution of the setback is also possible. In addition, in special cases, one of the joining partners can be provided with a seam surface that has no setback relative to each other, and the setback is provided only for the other joining partner. Therefore, only this setback provides the surface separation.

[0049] In engineering step c), the positioning of the actuating cylinder component and the attachment part for forming the pre-assembly is carried out by causing butt joints on the lower weld line surface and surface separation on the upper weld line surface.

[0050] For this purpose, the joining partners are preferably pressed axially against each other, whereby the lower weld line surfaces are in pressure contact with each other. Here, the two joining partners are also aligned along the longitudinal axis corresponding to the desired subsequent position of the attachment part with respect to the longitudinal axis of the actuating cylinder assembly. Thereafter, the positional relationship thus established is preferably maintained during further engineering steps until they are completed.

[0051] In engineering step d), the lower weld line surface is laser welded by a laser beam by creating a laser weld line in the lower weld line zone.

[0052] According to the present invention, the upper weld line space formed by the surface separation of the upper weld line surface provides unobstructed access for the laser beam up to the upper start of the lower weld line zone. Preferably, the laser beam penetrates exactly into the flat plane defined by the butt joints of the lower weld line surface and melts the seam surface in their surface area, thereby providing a thin flat melt which, after solidification, joins the joining partners in the form of a positive substance at the lower weld line surface and forms a laser weld line. In engineering step d), the laser weld line is produced without the addition of a welding filler material.

[0053] According to the present invention, the heat of solidification is at least partially dissipated upwards into the upper weld line zone in this process. This has the advantage of heating the upper weld line zone and removing the energy per unit length input into the lower weld line zone, thereby avoiding undesirable strong heating in the surrounding area of the lower weld line zone.

[0054] In engineering step e), laser-hybrid welding of the upper weld line surface is performed. The upper weld line surface is welded by laser-hybrid welding by means of a laser beam, the supply of a welding filler material, and the filling of the upper weld line space between the upper weld line surfaces.

[0055] In the upper weld line zone already preheated in engineering step d), the upper weld line surface is further heated until it begins to melt by the renewed application of a laser beam. According to the invention, a welding filler material is preferably added via a welding wire, melted, forms part of the melt in the upper weld line zone, fills the upper weld line space existing between the upper weld line surfaces, and thereby is directly connected to the upper weld line surfaces.

[0056] After the upper weld line space is filled with the melt, the application of the laser beam is terminated, and then the upper weld line zone is cooled to solidify the melt in the upper weld line space and form an indirect positive material joint between the upper weld line surfaces, thereby forming a hybrid weld. The indirect positive material connection is based on the fact that the positive material connection between the upper weld line surfaces is mediated by the solidified melt together with the involvement of the welding filler material.

[0057] As a result of performing all engineering steps, a welded and joined working cylinder assembly showing a laser-laser hybrid weld line according to the invention is obtained.

[0058] The invention also covers the case where engineering step e) is repeated, thereby filling the upper weld line space with the welding filler material layer by layer.

[0059] The advantages described for the welded actuator cylinder assembly according to the invention correspondingly also apply to the method. In particular, due to the low energy input per unit length and the very narrow melting zone at the lower weld line surface, solidification occurs advantageously in process step d) when the upper weld line zone, where solidification is caused by surface separation between the upper weld line surfaces, has not yet solidified in the upper weld line space. Thus, the connection between the joining partners has already occurred, which determines their positional relationship and protects them against distortion by the subsequent solidification of the upper weld line zone. The same advantages explained by the importance of using a laser welding system with lower power are simultaneously achieved in the method.

[0060] The laser-hybrid weld line of the upper weld line zone always refers to one point and is preferably formed with a time delay of 2 to a maximum of 10 seconds before the laser weld line of the lower weld line zone is formed.

[0061] For rotationally symmetric components, i.e., when the upper weld line surface is provided as an outer circular ring surface, increased bending stiffness is achieved without additional means at the weld line. This preferred embodiment is based on the fact that the lower laser weld line has already solidified and thermally contracted when the upper laser-hybrid weld line is formed. The subsequent thermal contraction of the upper hybrid weld line here causes an elastic prestress in the upper weld line zone surface, which is the outer circular ring surface. This is assisted by the fact that the upper weld line zone is wider than the butt joint provided lower weld line zone due to surface separation of the upper weld line surface, and thus the thermal contraction of the upper weld line zone is stronger than that of the lower weld line zone. The degree of prestress can be advantageously adjusted as required by the surface ratio between the lower weld line zone surface and the upper weld line zone surface and by the surface separation of the upper weld line surface, and thus an assembly of actuator cylinder components and attachment parts with improved mechanical properties can be obtained.

[0062] According to a further advantageous development, a method for manufacturing a welded actuating cylinder assembly is characterized in that the energy input per unit length applied in process step d) in the lower weld line zone is lower with respect to the lower weld line zone surface than the energy input per unit length applied in process step e) in the upper weld line zone with respect to the upper weld line zone surface.

[0063] Advantageously, the lower energy input per unit length in the lower weld line zone in process step d) compared to the energy input per unit length in the upper weld line zone in process step e), with respect to the weld line zone surface, ensures that solidification occurs earlier in the lower weld line zone than in the upper weld line zone and that the positional relationship of the joining partners is already stabilized when the distortion forces act on the joining partners due to solidification in the upper weld line zone.

[0064] According to the next advantageous development, a method for manufacturing a welded actuating cylinder assembly is characterized in that the energy input per unit length in process step d) in the lower weld line zone simultaneously meets the melting requirements of the welding filler material for the upper weld line zone. Thus, the welding of each of the two weld line zones can be carried out at the same laser power and at the same speed.

[0065] According to a further development, a method for manufacturing a welded actuating cylinder assembly is characterized in that the lower weld line surface is designed as an inner circular surface or an inner ring surface, the upper weld line surface is designed as an outer ring surface that radially surrounds the inner circular surface or the inner ring surface, the movement of the pre-assembly relative to the laser in process step d) is carried out by rotation of the pre-assembly, and the movement of the pre-assembly relative to the laser in process step e) is carried out by further rotation of the pre-assembly.

[0066] The advantages of the method according to the invention are particularly effective due to the rotationally symmetric coupling sections of the actuating cylinder components and the attachment parts. After the coupling partners are joined to the pre-assembly and fixed in their relative positions, they can be guided and welded by rotation under the laser, whereby the laser can be applied in a reliable and uniform manner. Thus, the laser weld line is formed by the first rotation according to process step d). After completion of the 360-degree rotation, a further full rotation is carried out and the welding filler material is supplied to the upper weld line space. At this time, the laser beam impinges on the welding filler material, thereby generating a melt, which fills the upper weld line space and directly connects the upper weld line surface in the form of a positive substance. After completion of the second full rotation, the laser hybrid weld line is also formed according to process step e).

[0067] According to another further development, a method for manufacturing a welded actuating cylinder assembly is characterized in that process step d) and process step e) are carried out simultaneously in parallel, the relative movement of the pre-assembly is carried out along the weld line, and the laser beam according to process step e) is offset along the direction of the relative movement with respect to the laser beam according to process step d). This further development requires the use of two laser beams and enables a further improvement in their efficiency.

[0068] According to this further development, the method is carried out by two laser beams that are applied simultaneously but linearly offset along the feed movement. Together with the linear speed of the laser welding, the spatial offset enables the accurate adjustment of the temporal offset of the laser application in the lower weld line zone and the upper weld line zone at the same linear position of the weld line, and enables the optimization of the weld formation. In particular, it is possible to keep the temporal offset sufficiently short for extremely large assemblies.

[0069] The invention is illustrated by way of example embodiments with reference to the following drawings.

Brief Description of the Drawings

[0070]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

[0071] In this context, the same reference numbers in the various drawings always refer to the same features or components. The reference numbers are also used in the description even if they are not shown in the corresponding drawings.

[0072] FIG. 1 shows an overall view of an operating cylinder assembly, which is a differential operating cylinder in an exemplary embodiment. In the exemplary embodiment, the operating cylinder component 1 is designed as both a piston rod 1.1 and a closure part 1.2. The piston rod 1.1 and the closure part 1.2 are each connected to the mounting part 2, in this case a spherical bearing, by a welding line 3.

[0073] Figure 1 also shows that the cylinder tube 1.4 is designed as an actuating cylinder component 1 which is connected on both sides by welding seams 3 to a closure part 1.2 which in this case is the lower closure part and to the other closure part 1.3 which in this case is the guide closure part. In this embodiment, the welding seam 3 between the cylinder tube 1.4 and the closure part 1.2 which is the lower closure part is vertical, and the welding seam 3 between the cylinder tube 1.4 and the other closure part 1.3, here the guide closure part, is inclined at a welding angle.

[0074] Figure 2 shows the joining partner parts 1, 2 before joining to form the pre-assembly after process step b) and in process step c).

[0075] Figure 3 shows the joined joining partner parts 1, 2 to form the pre-assembly in process step c).

[0076] In the following, Figures 2 and 3 are explained together. In the subsequent lower welding seam zone 4, the lower actuating cylinder component welding seam surface 4.1 and the lower mounting part welding seam surface 4.2 face each other as the lower welding seam surfaces 4.1, 4.2, and in the upper welding seam zone 5, the upper actuating cylinder component welding seam surface 5.1 and the upper mounting part welding seam surface 5.2 face each other as the upper welding seam surfaces 5.1, 5.2. The lower welding seam surfaces 4.1, 4.2 form the subsequent lower welding seam zone surface 4.4, and the upper welding seam surfaces 5.1, 5.2 form the subsequent upper welding seam zone surface 5.4. After the joining in process step d), the lower welding seam surfaces 4.1, 4.2 form a butt joint, and the upper welding seam surfaces 5.1, 5.2 form a surface separation 5.3. The upper welding seam space 5.4 is formed between the upper welding seam surfaces 5.1, 5.2 by the surface separation 5.3.

[0077] Figure 4 shows the weld line after welding when process steps d) and e) are carried out. Here, a narrow laser weld line is provided in the lower weld line zone 4. In the upper weld line zone 5, the upper weld line space 5.5 then has a filling of welding filler material 5.6 provided by the welding wire melted by the laser beam 6 at this time. At this time, both joining partners are connected in the form of a positive substance by the laser weld line in the lower weld line zone 4 and the hybrid weld line in the upper weld line zone 5.

[0078] Figures 5 and 6 show the method by which process steps d) and e) are successively carried out.

[0079] Figure 5 shows process step d) in which the pre-assembly is guided under the laser beam 6 in the movement direction indicated by the arrow. The laser beam 6 directly impinges on the lower weld line zone 4, penetrates the butting joint 4.3, and welds the lower weld line surfaces 4.1, 4.2. As shown in Figure 6, the laser beam 6 is then reapplied to carry out process step e), for which the pre-assembly already fixed and preheated by the lower weld line zone 4 is guided again in the movement direction indicated by the arrow. At the same time, welding filler material in the form of a welding wire is supplied and brought into the effective range of the laser beam 6 in the upper weld line space 5.5, where it is melted to form a weld pool that now fills the upper weld line space 5.5. After solidification, a completed weld line 3 consisting of the laser weld in the lower weld line zone 4 and the laser-hybrid weld line in the upper weld line zone 5 is provided.

[0080] Figure 7 schematically shows the parallel execution of process steps d) and e) in a modified exemplary embodiment. Here, the movement direction of the pre-assembly along the weld line 3 shown in a longitudinal section is indicated by the lower arrow. The laser beam 6 directly impinges on the lower weld line zone 4, penetrates the butting joint 4.3, and welds the lower weld line surfaces 4.1, 4.2.

[0081] The continuous movement of the joining partners 1, 2 causes them to enter the effective zone of the further laser beam 6. At the same time, the spatial distance creates a time distance dimensioned according to the movement speed, in particular such that heat is dissipated from the lower weld line zone 4 to the upper weld line zone 5, so that the molten material begins to solidify at the laser weld line in the lower weld line zone 4 and preheating is caused in the upper weld line zone 5. The further laser beam 6 captures the welding wire supplied in the upper weld line space 5.5, melts it, and at the same time and indirectly covers and melts the upper weld line surfaces 5.1, 5.2. The molten mass thus formed fills the weld line space 5.5, where it acts as the welding filler material 5.6 in the upper weld line zone 5. Thereby, after solidification, a laser-hybrid weld is formed.

[0082] Figure 8 is a schematic view of a method in an exemplary embodiment in which the lower weld line zone 4 is formed as an inner ring surface and the upper weld line zone 5 is formed as a concentric outer ring surface.

[0083] The left figure first shows in process step d) that the lower weld line zone 4 is generated as a laser weld line by the first rotation of the laser beam 6 until, after a 360-degree angular position, this zone becomes a completely closed inner ring surface in the longitudinal section with respect to the weld line.

[0084] The left figure then shows in process step e) that the laser beam 6 generates the upper weld line zone 5 as a laser-hybrid weld line by further rotation and addition of welding wire until this zone also forms a completely closed outer ring surface after a complete rotation.

[0085] Figure 8 shows two process steps, each after a rotation of approximately 240 degrees, together with arrows indicating the direction of rotation.

Explanation of symbols

[0086] 1 Actuating cylinder component 1.1 Piston rod 1.2 Closure part 1.3 Further closure part 1.4 Cylinder tube 2 Attachment part 3 Weld line 3.4 Total weld line area 4 Lower weld line zone 4.1 Lower operating cylinder component weld line area 4.2 Lower attachment part weld line area 4.3 Butt joint 4.4 Lower weld line zone area 5 Upper weld line zone 5.1 Upper operating cylinder component weld line area 5.2 Upper attachment part weld line area 5.3 Surface separation 5.4 Upper weld line zone area 5.5 Upper weld line space 5.6 Filling of welding filler material 6 Laser

Claims

1. A welded actuating cylinder, comprising: an actuating cylinder component (1), an attachment part (2), and a weld line (3), wherein the actuating cylinder component (1) is designed as a piston rod (1.1) or a closure part (1.2), and the attachment part (2) is designed as a coupling module designed to be coupled to a device for being actuated for force transmission, in the welded actuating cylinder, wherein the weld line (3) is designed as a hybrid weld line manufactured in stages, having a lower weld line zone (4) and an upper weld line zone (5), in the lower weld line zone (4), the actuating cylinder component (1) has a lower actuating cylinder component weld line surface (4.1), the attachment part (2) has a lower attachment part weld line surface (4.2), the lower weld line surfaces (4.1, 4.2) have a butt joint (4.3), and the lower weld line zone (4) is designed as a laser weld line, in the upper weld line zone (5), the actuating cylinder component (1) has an upper actuating cylinder component weld line surface (5.1), the attachment part (2) has an upper attachment part weld line surface (5.2), the upper weld line surfaces (5.1, 5.2) have a surface separation (5.3), the upper weld line zone (5) is formed as a laser - hybrid weld line, and is characterized in that it has a filling of welding filler metal (5.6) in an upper weld line space (5.5) formed by the surface separation (5.3).

2. A welded actuating cylinder assembly, comprising: an actuating cylinder component (1), an attachment part (2), and a weld line (3), wherein the actuating cylinder component (1) is designed as a cylinder tube (1.4), and the attachment part (2) is designed as a closure part (1.2) or a further closure part (1.3), in the welded actuating cylinder assembly, wherein the weld line (3) is formed as a hybrid weld line manufactured in stages, having a lower weld line zone (4) and an upper weld line zone (5), In the lower welding line zone (4), the actuating cylinder component (1) has a lower actuating cylinder component welding line surface (4.1), the attachment part (2) has a lower attachment part welding line surface (4.2), the lower welding line surfaces (4.1, 4.2) have a butt joint (4.3), and the lower welding line zone (4) is designed as a laser welding line. In the upper welding line zone (5), the actuating cylinder component (1) has an upper actuating cylinder component welding line surface (5.1), the attachment part (2) has an upper attachment part welding line surface (5.2), the upper welding line surfaces (5.1, 5.2) have a surface separation (5.3), the upper welding line zone (5) is formed as a laser - hybrid welding line, and the welded joint actuating cylinder assembly is characterized in that it has filling of a welding filler material (5.6) in the upper welding line space (5.5) formed by the surface separation (5.3).

3. The lower welding line zone surface (4.4) and the upper welding line zone surface (5.4) form a total welding line surface (3.4), and the surface ratio of the lower welding line zone surface (4.4) to the total welding line zone surface (3.4) is 15% - 40%. The welded joint actuating cylinder assembly according to claim 1 is characterized by this.

4. The surface separation (5.3) in the upper welding line zone (5) is 0.5 mm - 2.0 mm. The welded joint actuating cylinder assembly according to any one of claims 1 to 3 is characterized by this.

5. The lower welding line zone surface (4.4) is formed as an inner circular surface or a ring surface, and the upper welding line zone surface (5.4) is formed as an outer ring surface that radially surrounds the lower welding line zone surface (4.4). The welded joint actuating cylinder assembly according to any one of claims 1 to 4 is characterized by this.

6. A method for manufacturing a welded joint actuating cylinder assembly, wherein the actuating cylinder assembly includes an actuating cylinder component (1) and an attachment part (2). a) Providing the actuating cylinder component (1) and the attachment part (2). b) A step of manufacturing a lower-actuating cylinder component weld surface (4.1), a lower attachment portion weld surface (4.2), an upper-actuating cylinder component weld surface (5.1), and an upper attachment portion weld surface (5.2), wherein at least one of the upper weld surfaces (5.1, 5.2) is set back with respect to each of the lower weld surfaces (4.1, 4.2); c) A step of manufacturing the butt joint (4.3) of the lower weld surfaces (4.1, 4.2) and positioning the actuating cylinder component (1) and the attachment portion (2) to form a pre-assembly by generating a surface separation (5.3) of the upper weld surfaces (5.1, 5.2); d) A step of laser-welding the lower weld surfaces (4.1, 4.2) with a laser beam by manufacturing a laser weld line in the lower weld zone (4); e) A step of hybrid-welding the upper weld surfaces (5.1, 5.2) by means of a laser beam, supply of a welding filler material, and filling of an upper weld line space (5.5) between the upper weld surfaces (5.1, 5.2) in the upper weld zone (5). A method for manufacturing a welded actuating cylinder assembly including these steps.

7. The method for manufacturing a welded actuating cylinder assembly according to claim 6, characterized in that, in step d) of the process steps, the energy input per unit length in the lower weld zone (4) is lower with respect to the lower weld zone surface (4.4) than the energy input per unit length in step e) in the upper weld zone (5) with respect to the upper weld zone surface (5.4).

8. The lower weld zone surface (4.4) is designed as an inner circular surface or an inner ring surface, and the upper weld zone surface (5.4) is designed as an outer ring surface that radially surrounds the lower weld zone surface (4.4). In step d) of the process steps, the movement of the pre-assembly with respect to the laser beam (6) is performed by rotation of the pre-assembly. In step d) of the process steps, the movement of the pre-assembly with respect to the laser beam (6) is performed by rotation of the pre-assembly. The method for manufacturing a welded actuating cylinder assembly according to claim 5 or 6, characterized in that, in said process step e), the movement of said pre-assembly relative to said laser is effected by a further rotation of said pre-assembly.

9. The method for manufacturing a welded actuating cylinder assembly according to any one of claims 5 to 7, characterized in that said process step d) and said process step e) are carried out in parallel, the relative movement of said pre-assembly being effected along said welding line (3), and the laser beam (6) according to said process step e) being offset with respect to the laser beam according to said process step d) along the direction of said relative movement.

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