Sheet steel component for a working device of a working machine and method for producing a sheet steel component of this kind

Abstract

The invention relates to a sheet steel component (10) for a working device of a working machine, which sheet steel component has at least one receptacle (14) for a bearing element, in particular a receptacle (14) for a bolt. According to the invention, the at least one receptacle (14) is formed as a region of the sheet steel component (10) that surrounds the circumference of an opening (18), wherein said region has a sheet metal portion (20) having a sheet metal thickness d and a drawn collar (22) which adjoins the sheet metal portion (20) and extends in the axial direction (24) of the opening (18). The invention further relates to a use of the sheet steel component as a device component of a working device of a working machine, to a device unit for a working device of a working machine, having at least one sheet steel component (10) of this kind, and to a corresponding method for producing a sheet steel component (10) for a working device of a working machine having a receptacle (14) for a bearing element.

Description

[0001] Sheet steel component for a working device of a work machine and method for producing such a sheet steel component

[0002] The invention is based on a sheet steel component for a working device of a work machine, which has at least one receptacle for a bearing element, in particular a receptacle for a bolt.

[0003] The invention further relates to a use of the sheet steel component as a device component of a working device of a work machine, a device unit of a working device of a work machine with at least one sheet steel component and a corresponding method for producing a sheet steel component for a working device of a work machine, wherein this sheet steel component has at least one receptacle for a bearing element, in particular a receptacle for a bolt.

[0004] Countless types of work machines are used in construction, forestry, and agriculture. In the construction industry, for example, there are cranes, excavators, wheel loaders, etc. These each have a work tool consisting of several units. These include, for example, an attachment / tool ​​(e.g., a shovel), an arm, a hydraulic cylinder, etc. Some of the units are pivotably mounted to one another. The units have bearing elements that together form a corresponding bearing for the pivoting movement.

[0005] Document DE 11 2022 000 499 T5 describes a work machine in the form of a hydraulic excavator, which, in addition to the work machine base with travel and rotating unit, also comprises a work device. This work device, in turn, has a boom, an arm, a bucket, an arm cylinder, and a bucket cylinder as device units. The arm comprises, among other things, an arm cylinder mount with corresponding sheet steel components and a bucket cylinder mount with corresponding sheet steel components, each of which has a receptacle for a bolt for pivotally supporting one end of the arm cylinder and a bolt for pivotally supporting one end of the bucket cylinder, respectively. To ensure that the mount has a sufficiently large connection surface for the connection to the bolt, the base plates of the sheet steel components are each "doubled up" with a reinforcement plate, which, however, presents some challenges.

[0006] The object of the invention is to provide a sheet steel component for a working device of a work machine with a holder for a bearing element, a device unit of a working device with at least one such sheet steel component and a method for producing such a sheet steel component, in which reinforcement of the starting sheet by an additional part can be dispensed with.

[0007] According to the invention, the object is achieved by the features of the independent claims. Preferred embodiments of the invention are specified in the subclaims, each of which may represent an aspect of the invention individually or in combination.

[0008] In the sheet steel component according to the invention for a working device of a work machine, which has at least one receptacle for a bearing element, in particular a receptacle for a bolt, it is provided that the at least one receptacle is formed as a region of the sheet steel component that circumferentially surrounds an opening, wherein this region has a sheet metal section with a sheet thickness d and a drawn collar that adjoins the sheet metal section and extends in the axial direction of the opening. In this way, it can be ensured that the receptacle for the bearing element has a sufficiently large connection surface for the connection to the bearing element, which is of great importance in particular for a connection via surface pressure.

[0009] The sheet steel component is manufactured from a sheet steel blank, usually made from hot-rolled steel. The steel used for this sheet steel is often a structural steel, as standardized in EN 10025.

[0010] According to a preferred embodiment of the invention, the sheet thickness d is in the range 20 mm < d < 40 mm. Such a sheet thickness is quite typical for sheet steel components in the working equipment of work machines. Examples of such work machines include excavators and wheel loaders.

[0011] According to a further preferred embodiment of the invention, the collar projects beyond the sheet metal section by at least half the sheet metal thickness d. This combination of the sheet metal section of sheet metal thickness d and the adjoining drawn collar can completely form the receptacle for the bearing element at said sheet metal thickness d, in particular at 25 mm < d < 40 mm.

[0012] According to yet another preferred embodiment of the invention, the steel of the sheet steel component has the following composition (in weight %): at least 0.05 to a maximum of 0.25 carbon (C), at least 0.10 to a maximum of 0.45 silicon (Si), at least 0.80 to a maximum of 2.00 manganese (Mn), and optionally one or more of the following elements: up to a maximum of 0.030, preferably up to 0.015 nitrogen (N), up to a maximum of 0.10, preferably up to 0.025 phosphorus (P), up to a maximum of 0.020, preferably up to 0.010 sulfur (S), up to a maximum of 0.010, preferably up to 0.005 boron (B), up to a maximum of 0.60 copper (Cu), up to a maximum of 0.60 nickel (Ni), up to a maximum of 0.45 chromium (Cr), up to a maximum of 0.25 vanadium (V), up to a maximum of 0.10 titanium (Ti), up to a maximum of 0.10 Niobium (Nb), up to a maximum of 0.25 molybdenum (Mo) and up to a maximum of 0.25 aluminum (AI),

[0013] Rest iron and usual steel-related impurities caused by melting.

[0014] Typically, this steel is unalloyed or micro-alloyed steel. Such steel possesses sufficient strength, is sufficiently formable and machinable, and has proven itself as a material for such sheet steel components.

[0015] Furthermore, it is preferably provided that the collar has a circular-cylindrical contour. This is intended, in particular, for receiving a bolt.

[0016] The invention further relates to the use of the aforementioned sheet steel component for a working device of a work machine. The sheet steel component is a device component of the working device of the work machine. The invention further relates to a device unit for a working device of a work machine with at least one aforementioned sheet steel component, which has at least one receptacle for a bearing element. By means of this device unit, the corresponding working device for a work machine forms an assembly which comprises this device unit and a further unit of the work machine mounted on this device unit via at least one bearing, wherein the bearing element is part of the bearing. The device unit with the sheet steel component is in particular an attachment or tool, an arm, a lever mechanism or a boom. The further unit is in particular a further device unit of the working device.Alternatively, the working device of the work machine itself can be regarded as a device unit.

[0017] In the method according to the invention for producing a sheet steel component for a working device of a work machine, in particular a sheet steel component mentioned above, which has at least one receptacle for a bearing element, the following steps are provided:

[0018] (i) Providing a steel sheet blank with a sheet thickness d,

[0019] (ii) Creating at least one opening through the steel sheet blank and

[0020] (iii) forming the sheet steel blank into the sheet steel component, wherein the at least one receptacle is produced by collar drawing or combined collar and ironing at the opening.

[0021] The invention thus provides a forming process that makes it possible to completely or partially eliminate the need for additional sheets or pipe sections to provide a sufficient length, since the collar drawing process can increase the surface area, which, depending on the application, makes additional sheets or pipes entirely or partially unnecessary. The collar can often be extended to twice the sheet thickness (and sometimes slightly more). Depending on the application, structural steels are predominantly used, which are also ideally suited for this purpose due to their forming properties. As the strength increases, the collar height decreases.

[0022] The following additional advantages arise: Collars can be produced with minimal effort, eliminating welding and the associated quality assurance. This prevents distortion and also eliminates the need for a heat-affected zone, which creates a metallurgical notch. Less logistics effort and master data maintenance are required due to the elimination of an additional part. Work hardening during forming can potentially improve the wear behavior of the holder. Weight savings and the associated CO2 savings are also notable advantages.

[0023] It is preferably provided that the sheet thickness d is in the range 20 mm < d < 40 mm.

[0024] With sheet thicknesses d in this (thickness) range, undesirable cracks can easily form in the collar area. It has been found that the basis for the formation or the basic prerequisite for the prevention of such cracks arises during the original creation of at least one opening through the steel sheet blank. For example, punching a hole through the blank has proven to be rather unfavorable. According to a preferred embodiment of the method according to the invention, the original creation of the respective opening through the steel sheet blank is carried out using one of the techniques listed below:

[0025] (a) by water jet cutting,

[0026] (b) by laser cutting and

[0027] (c) by creating a channel-shaped opening through the steel sheet blank and then drilling and / or milling the channel to the desired size. The channel is created, for example, by burning out.

[0028] According to a further preferred embodiment of the method according to the invention, it is provided that the receptacle is produced in one operation using a drawing punch and a drawing ring, wherein the drawing gap between the drawing punch and the drawing ring in the alternative with the ironing drawing is narrower than the initial sheet thickness of the steel sheet blank, so that when the steel sheet material of the steel sheet blank is drawn into the drawing ring, the steel sheet material is ironed.

[0029] In particular, it is provided that the drawing punch used has a truncated cone-shaped punch head.

[0030] The steel of the steel sheet blank advantageously has the following composition (in weight %): at least 0.05 to a maximum of 0.25 carbon (C), at least 0.10 to a maximum of 0.45 silicon (Si), at least 0.80% to a maximum of 2.00% manganese (Mn), and optionally one or more of the following elements: up to a maximum of 0.030, preferably up to 0.015 nitrogen (N), up to a maximum of 0.10, preferably up to 0.025 phosphorus (P), up to a maximum of 0.020, preferably up to 0.010 sulfur (S), up to a maximum of 0.010, preferably up to 0.005 boron (B), up to a maximum of 0.60 copper (Cu), up to a maximum of 0.60 nickel (Ni), up to a maximum of 0.45 chromium (Cr), up to a maximum of 0.25 vanadium (V), up to a maximum of 0.10 titanium (Ti), up to a maximum of 0.10 niobium (Nb), up to a maximum of 0.25 molybdenum (Mo) and up to a maximum of 0.25 aluminum (AI),

[0031] Rest iron and usual steel-related impurities caused by melting.

[0032] Finally, it is advantageous that the forming of the sheet steel blank, at least the collaring or the combined collaring and ironing of the holder, takes place below the austenitizing temperature. For this purpose, room temperature can be used (this is usually a temperature in the range of approximately 17°C to 25°C) or warm forming can be carried out at a temperature in the range of 100°C to 600°C.

[0033] Accordingly, it is preferably provided that for forming at least one forming region of the steel sheet blank surrounding the opening is heated to a temperature (forming temperature) in a range from 60 °C to 800 °C, preferably from 100 °C to 600 °C.

[0034] Heating to the forming temperature can be achieved, for example, inductively, conductively, or by means of radiant heat. Preferably, heating is carried out inductively, i.e., by inductive heating or heating. For this purpose, a suitable induction coil is preferably inserted into the opening.

[0035] The invention will now be explained by way of example with reference to the accompanying drawings using a preferred embodiment, wherein the features presented below may represent an aspect of the invention both individually and in combination. They show:

[0036] Fig. 1 shows a sheet steel component for a working device of a working machine according to a preferred embodiment of the invention with a receptacle for a bearing element in a side view and

[0037] Fig. 2 is a sectional view through the sheet steel component of Fig. 1 along the section line A - A.

[0038] Fig. 1 shows a sheet steel component 10 for a (not shown) working device of a work machine, more precisely for a device unit of such a working device. The sheet steel component 10 has, in addition to a sheet metal base 12, a receptacle 14 in the form of a bushing for a (not shown) bearing element in the form of a bolt. The sheet metal base 12 shown here is flat and can be connected to the rest of the corresponding device unit via one of its edges 16. The receptacle 14 is formed as a region of the sheet steel component 10 that circumferentially surrounds an opening 18. This region, which forms the receptacle, is composed of a sheet metal section 20 (shown in Fig. 2) of the sheet metal base 12 and a drawn collar 22.

[0039] The sheet metal section has a sheet thickness d which – depending on the specific application – lies in the range 20 mm < d < 40 mm, and the drawn collar 22 adjoins the sheet metal section 20 on one side and extends in the axial direction 24 of the opening 18. The collar 22 has a circular-cylindrical contour. The sheet metal thickness of the sheet metal section 20 essentially corresponds to the (initial) sheet metal thickness d of a sheet steel blank from which the sheet steel component 10 is manufactured. It should be noted at this point that the illustrations in the figures are not to be understood as strictly to scale. The corresponding work machine can be a work machine from the construction, forestry and / or agricultural sectors. An example here is a wheel loader or farm loader. This has a work device that is composed of several equipment units.In a wheel loader, these include: a bucket as an attachment / tool, an arm, a lever mechanism arranged between the arm and bucket, and one or more hydraulic cylinders (e.g., lifting and tilting cylinders). Some of these units are pivotably mounted to one another. The units have bearing elements that together form a corresponding bearing for the pivoting movement.

[0040] Fig. 2 shows a sectional view through the sheet steel component of Fig. 1 along the axis A - A. In this view, it is particularly clear that the opening 18 extends completely through the steel component 10 from one side 24 to the other side 26. Furthermore, it is clearly visible that the collar 22 projects beyond the sheet metal section 20 of the sheet metal base 12 by the full sheet thickness d or slightly more than this. The receptacle 14 in the form of a bushing thus has a receptacle length L along the axial direction 24 of the opening 18, which is generally up to twice as long as the sheet metal thickness d itself. The collar 22 has a wall thickness w that is significantly less than the sheet metal thickness d.

[0041] The following process steps are provided for the production of this sheet steel component 10 for a working device of a work machine:

[0042] (i) Providing a steel sheet blank (not shown) with a sheet thickness d,

[0043] (ii) Creating at least one opening 18 through the steel sheet blank as a kind of pilot hole and

[0044] (iii) Forming the sheet steel blank into the sheet steel component 10, wherein the at least one receptacle 14 is created by collar drawing or combined collar and ironing at the opening 18. The corresponding tool comprises a drawing punch and a drawing ring.

[0045] To produce a sheet steel component 10 in which the wall thickness w of the drawn collar 22 is approximately the same as the sheet thickness d of the steel blank, collar drawing is suitable, and to produce a sheet steel component 10 in which the wall thickness w of the drawn collar 22 is significantly smaller than the sheet thickness d of the steel blank, combined collar and ironing at the opening 18 is suitable.

[0046] Here, the receptacle 14 is created in a single operation using the drawing punch and the drawing ring. During collar and ironing drawing, a drawing gap between the drawing punch and the drawing ring is selected that is narrower than the starting sheet thickness d of the steel sheet blank, so that when the steel sheet material of the steel sheet blank is drawn into the drawing ring, the steel sheet material is ironed. The sheet steel component according to the invention can be used for all areas of so-called yellow goods, i.e., work machines or transport machines with work equipment, in which bolts or other bearing elements must not exceed a certain surface pressure that cannot be achieved by the sheet thickness d of the sheet steel component 10 alone.

[0047] Reference symbol

[0048] 10 sheet steel component

[0049] 12 Sheet metal base 14 Holder

[0050] 16 edge

[0051] 18 Breakthrough

[0052] 20 sheet metal sections

[0053] 22 drawn collar 24 axial direction (collar)

[0054] 26 one side (sheet steel component)

[0055] 28 other side (steel sheet component) d sheet thickness

[0056] L Mounting length w Wall thickness of the collar

Claims

Patent claims 1. Sheet steel component (10) for a working device of a work machine, which has at least one receptacle (14) for a bearing element, in particular a receptacle (14) for a bolt, characterized in that the at least one receptacle (14) is formed as a region of the sheet steel component (10) which circumferentially surrounds an opening (18), this region having a sheet metal section (20) with a sheet metal thickness d and a drawn collar (22) which adjoins the sheet metal section (20) and extends in the axial direction (24) of the opening (18).

2. Sheet steel component according to claim 1, characterized in that the sheet thickness d is in the range 20 mm < d < 40 mm.

3. Sheet steel component according to claim 1 or 2, characterized in that the collar (22) projects beyond the sheet metal section (20) by at least half the sheet metal thickness d.

4. Sheet steel component according to one of claims 1 to 3, characterized in that the steel of the sheet steel component (10) has the following composition (in weight %): at least 0.05 to a maximum of 0.25 carbon (C), at least 0.10 to a maximum of 0.45 silicon (Si) and at least 0.80 to a maximum of 2.00 manganese (Mn), and optionally one or more of the following elements (in weight %): up to a maximum of 0.030 nitrogen (N), up to a maximum of 0.10 phosphorus (P), up to a maximum of 0.020 sulfur (S), up to a maximum of 0.010 boron (B), up to a maximum of 0.60 copper (Cu), up to a maximum of 0.60 nickel (Ni), up to a maximum of 0.45 chromium (Cr), up to a maximum of 0.25 vanadium (V), up to a maximum of 0.10 titanium (Ti), up to a maximum of 0.10 niobium (Nb), up to a maximum of 0.25 molybdenum (Mo) and up to a maximum of 0.25 aluminum (AI), Rest iron and usual steel-related impurities caused by melting.

5. Sheet steel component according to one of claims 1 to 4, characterized in that the collar (22) has a circular-cylindrical contour.

6. Use of the sheet steel component according to one of claims 1 to 5 as a component of a working device of a work machine.

7. Device unit for a working device of a work machine, with at least one sheet steel component (10) according to one of claims 1 to 5, which has at least one receptacle (14) for a bearing element.

8. A method for producing a sheet steel component (10) for a working device of a work machine, in particular a sheet steel component (10) according to one of claims 1 to 5, which has at least one receptacle (14) for a bearing element, in particular a receptacle for a bolt, comprising the steps: Providing a sheet steel blank with a sheet thickness d, creating at least one opening (18) through the sheet steel blank and forming the sheet steel blank into the sheet steel component (10), wherein the at least one receptacle (14) is produced by collar drawing or combined collar and ironing at the opening (18).

9. Method according to claim 8, characterized in that the sheet thickness d is in the range 20 mm < d < 40 mm.

10. Method according to claim 8 or 9, characterized in that the initial creation of the respective opening (18) through the steel sheet blank is carried out by means of one of the following techniques: by water jet cutting, by laser beam cutting and by creating an opening (18) in the form of a channel through the steel sheet blank and subsequently drilling and / or milling the opening (18) to a desired size.

11. Method according to one of claims 8 to 10, characterized in that the receptacle (14) is produced in one operation with the aid of a drawing punch and a drawing ring, wherein the drawing gap between the drawing punch and the drawing ring in the alternative with ironing is narrower than the sheet thickness d of the steel sheet blank, so that when the steel sheet material of the steel sheet blank is drawn into the drawing ring, ironing of the steel sheet material takes place.

12. Method according to one of claims 8 to 11, characterized in that the forming of the steel sheet blank, at least the collar drawing or the combined collar and ironing drawing to form the receptacle (14), takes place at a forming temperature below the austenitizing temperature, preferably < 600 °C, particularly preferably at room temperature.

13. Method according to one of claims 8 to 12, characterized in that at least one forming region of the steel sheet blank surrounding the opening (18) is heated for forming to a temperature in a range from 60 °C to 800 °C, preferably from 100 °C to 600 °C.

14. The method according to claim 13, characterized in that the heating is carried out by inductive heating.

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