ADDITIVELY MANUFACTURED COMPONENT WITH INSERT THREAD, MANUFACTURING METHOD FOR THE SAME AS WELL AS COMPONENT WITH WIRE THREAD INSERT INSTALLED IN THE INSERT THREAD

Abstract

Additive manufacturing method of a component with a thread opening and an insert thread at its radial inner wall, for a wire thread insert to form a standard thread. A 3D component drawing includes the thread opening and the insert thread arranged in there, which is defined by

[00001]$D_{HC}\ge D_{\mathrm{HC}\min }=d+0.75\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}$$D_{1HC}\ge D_{1\mathrm{HC}\min }=d+0.125\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}$$D_{1HC}\le D_{1\mathrm{HC}\max }=d+0.125\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}+0.373\times P-0.192\times P^{1.21}$$P_{HC}=\left(D_{\mathrm{HC}\min }-D_{1\mathrm{HC}\min }\right)\times 1.6\times \tan \left(\frac{\alpha }{2}\right)$

with d nominal diameter of the screw thread α flank angle of the screw thread P pitch of the screw thread D.sub.HC nominal diameter of the insert thread D.sub.HC min smallest nominal diameter of the insert thread D.sub.1HC core diameter of the insert thread D.sub.1HC min smallest core diameter of the insert thread D.sub.1HC max largest core diameter of the insert thread P.sub.HC pitch of the insert thread.
Dimensions of the insert thread are adapted with correction factors. The drawing is converted with the adapted dimensions into a model for the component manufacturing.

Claims

1. An additive manufacturing method of a component with a thread opening and an insert thread arranged to its radial inner wall, which is adapted to a wire thread insert to be received for the purpose of reinforcing the thread, so as to form a standard thread from the insert thread and wire thread insert, with the manufacturing method including the following steps: providing a three-dimensional component drawing with the thread opening and the insert thread arranged in there, which is defined by $D_{HC}\ge D_{\mathrm{HC}\min }=d+0.75\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}$ $D_{1HC}\ge D_{1\mathrm{HC}\min }=d+0.125\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}$ $D_{1HC}\le D_{1\mathrm{HC}\max }=d+0.125\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}+0.373\times P-0.192\times P^{1.21}$ $P_{HC}=\left(D_{\mathrm{HC}\min }-D_{1\mathrm{HC}\min }\right)\times 1.6\times \tan \left(\frac{\alpha }{2}\right)$ with d nominal diameter of the screw thread to be received in the insert thread with wire thread insert α flank angle of the screw thread to be received in the insert thread with wire thread insert P pitch of the screw thread to be received in the insert thread with wire thread insert D.sub.HC nominal diameter of the insert thread D.sub.HC min smallest nominal diameter of the insert thread D.sub.1HC core diameter of the insert thread D.sub.1HC min smallest core diameter of the insert thread D.sub.1HC max largest core diameter of the insert thread P.sub.HC pitch of the insert thread adapting of dimensions of the insert thread to the additive manufacturing with the help of correction factors, converting the three-dimensional component drawing with the adapted dimensions into a layer model for the additive manufacturing and additive manufacturing of the three-dimensional component.

2. The manufacturing method according to claim 1, in which the adapting of the dimensions of the insert thread is made by expanding at least one of the following sizes: nominal diameter D.sub.HC, core diameter D.sub.1HC, flank angles α.sub.HC and pitch P.sub.HC.

3. The manufacturing method according to claim 2, in which the adapting of the nominal diameter D.sub.HC to an additive nominal diameter D.sub.AM, the adapting of the core diameter Dim to an additive core diameter D.sub.1AM, the adapting of the flank angle α.sub.HC to an additive flank angle α.sub.AM and the adapting of the pitch P.sub.HC to an additive pitch P.sub.AM take place on the basis of the following equations:
D.sub.AM=D.sub.HC*δ
D.sub.1AM=D.sub.1HC*δ.sub.1
α.sub.AM=α.sub.HC*δ.sub.α
P.sub.AM=P.sub.HC*δ.sub.P wherein δ, δ.sub.1, δ.sub.α, δ.sub.P are corresponding correction factors for the nominal diameter, the core diameter, the flank angle and the pitch.

4. The manufacturing method according to claim 3, wherein the correction factors have the following value ranges: TABLE-US-00003 correction factor: value range: δ 1.04-1.25 δ.sub.1 1.04-1.25 δ.sub.α 1.04-1.25 δ.sub.P 1.04-1.25

5. The manufacturing method according to claim 1, wherein for metric threads with α=60°, the above equations are applicable for d=2; 2.5; 3; 3.5; 4; 4.5; 5; 6; 7; 8; 9; 10; 11; 12; 14; 16; 18; 20 [mm].

6. The manufacturing method according to claim 5, wherein for metric threads with α=60°, the above equations are applicable for P=0.45; 0.5; 0.6; 0.7; 0.75; 0.8; 1; 1.25; 1.5; 1.75; 2; 2.5; 3 [mm].

7. The manufacturing method according to claim 1, wherein for inch threads with α=60°, the above equations are applicable for d=0.086; 0.099; 0.112; 0.125; 0.138; 0.164; 0.19; 0.216; 0.25; 0.3125; 0.375; 0.4375; 0.5; 0.5625; 0.625; 0.75; 0.875 [inch].

8. A manufacturing method of an additively manufactured component with a wire thread insert comprising the following steps: providing an additively manufactured component with an insert thread according to claim 1, and rotating a wire thread insert into the insert thread of the additively manufactured component whereby the diameter of the wire thread insert is reduced in comparison with a state in which the wire thread insert is not screwed in.

9. The manufacturing method according to claim 8, with the further step: screwing of a screw S with a nominal diameter d into a component opening of the additively manufactured component into the wire thread insert in the insert thread.

10. An additively manufactured component with a component opening and an insert thread arranged to an inner wall of the component opening, in which a wire thread insert is arranged, wherein the additively manufactured component is manufactured according to a manufacturing method according to claim 1.

11. The component according to claim 10 which is manufactured out of plastic material or of metal by means of a laser sinter method or laser melting method.

12. A component connection, having the following features: a first additively manufactured component with an insert thread, wherein the additively manufactured component is an additively manufactured component according to a manufacturing method according to claim 1, a wire thread insert arranged in the insert thread, a second component with a through opening and a screw S with a head, a shaft and a thread arranged on the shaft, wherein the shaft extends through the through opening and the thread of the shaft is screwed together with the first component via the wire thread insert that is arranged in the insert thread.

13. The component connection according to claim 12, in which the thread has a nominal diameter d on the shaft of the screw S and the insert thread has a core diameter D.sub.1HC according to D.sub.1HC≥d+0.46×P.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Embodiments of the present disclosure will be described in more detail based on the drawings, showing:

[0048] FIG. 1 an illustration of a standard inner thread in a component with geometry data,

[0049] FIG. 2 an illustration of a screw with screw thread or outer thread, respectively, with geometry specifications,

[0050] FIG. 3 an embodiment of an additively manufactured component in the process of the manufacturing with a component opening and an insert thread or inner thread, respectively,

[0051] FIG. 4 an enlarged schematic illustration of an additively manufactured thread section,

[0052] FIG. 5 an embodiment of a component composite of two components with a screw that is screwed into a component opening of an additively manufactured component having an insert thread with a wire thread insert,

[0053] FIG. 6 an embodiment of a component composite of two components, in which the additively manufactured component includes a thread bolt with an insert thread as outer thread on which a wire thread insert is arranged and subsequently, a female thread element is screwed on,

[0054] FIG. 7 a flow chart of a manufacturing method,

[0055] FIG. 8 a flow chart of a further manufacturing method,

[0056] FIG. 9 a flow chart of a further manufacturing method.

DETAILED DESCRIPTION

[0057] In the construction of components 10, female standard threads, i.e. an inner thread (see FIG. 1), as well as male standard threads, i.e. an outer thread (see FIG. 2) are equally used. In known application cases, a female standard thread forms an inner thread of a nut or a component opening. A male standard thread forms, for example, an outer thread on the shaft of a screw.

[0058] The accuracy to gauge of a female and a male standard thread is determined by the nominal diameter d; D; the core diameter d.sub.1; D.sub.1, the pitch P and the flank angle α.

[0059] A thread outside of tolerances stipulated by standards (e.g. a metric thread) causes a threading to become impossible or insecure. As exemplary explained in FIG. 4, additive manufacturing methods sometimes deviate significantly from a target thread curve. In FIG. 4, the target thread curve is illustrated with a dashed line and the additively manufactured thread curve is illustrated with a permanent line. In case of additively manufactured components with thread, no matter if in case of additively manufactured female or male threads, an insert thread 16 is manufactured additively in/at the component 10 and is combined with a wire thread insert 30 in order to achieve a standard thread that is true to size without any post-processing. This combination of additive insert thread 16 and wire thread insert 30 forms the advantageous standard thread which is necessary for a connection.

[0060] As an initial material for the additive manufacturing of a component with insert thread, plastic materials may be used. These materials include, for example, polyamide 11, polyamide 12, polyaryl etherketone, PEEK, PA6X, polypropylene, thermoplastic elastomers and polystyrol.

[0061] Furthermore, metallic materials for the additive laser sintering or laser melting may be used for the manufacturing of the component. Weldable metallic materials with a carbon equivalent of approx. 0.2 to 0.4 may be used. Aluminum, titanium and nickel base alloys (as for example Inconel) may be used as basic materials, beside steel.

[0062] In this context, the selective laser beam melting may be an additive process.

[0063] No demands are made on a material or a shape of the wire thread insert 30 that arranged in the insert thread 16. Known wire thread inserts 30 may be used in the insert thread. Also wire thread inserts 30 with amended cross-sectional profiles may be installed in the insert thread 16 of a component opening 12, i.e. in a thread opening, or of a male component. For this purpose, the flank angle, which may abut the additively manufactured insert thread 16, of the wire thread insert 30 is enlarged or decreased. In this way, a firm fit of the wire thread insert 30 may be realized in the insert thread 16, provided that the flank angle of the insert thread 16 is also adapted to the flank angle of the wire thread insert 30.

[0064] For the construction of a component 10 to be manufactured additively, with a component opening 12, an insert thread 16 is provided at an inner wall 14 of the component opening 12. As the additive manufacturing method realizes the component 10 in a three-dimensional manner in a layer construction, the component 10 with component opening 12 and insert thread 16 is constructed in a three-dimensional model and is drawn with common drawing programs, e.g. CAD.

[0065] The geometry of the insert thread 16 is adapted to a wire thread insert 30. Accordingly, a standard thread for female components, i.e. an inner thread (see FIG. 5) or for male components, i.e. an outer thread (see FIG. 6), arises from a combination of insert thread 16 and wire thread insert 30.

[0066] The geometry of the insert thread 16 is defined in DIN 8140 as of September 2021. Accordingly, the following applies to the geometry of the insert thread 16 as inner thread

[00006]$D_{HC}\ge d_{\mathrm{HC}\min }=D+0.75\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}$$D_{1HC}\ge d_{1\mathrm{HC}\min }=D+0.125\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}$$D_{1HC}\le d_{1\mathrm{HC}\max }=D+0.125\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}+0.373\times P-0.192\times P^{1.21}$$P_{HC}=\left(D_{\mathrm{HC}\min }-D_{1\mathrm{HC}\min }\right)\times 1.6\times \tan \left(\frac{\alpha }{2}\right)$ [0067] with [0068] d nominal diameter of the screw thread to be received in the inner thread [0069] α flank angle of the screw thread to be received in the inner thread [0070] P pitch of the screw thread to be received in the inner thread [0071] D.sub.HC nominal diameter of the insert thread [0072] D.sub.HC min smallest nominal diameter of the insert thread [0073] D.sub.1HC core diameter of the insert thread [0074] D.sub.1HC min smallest core diameter of the insert thread [0075] D.sub.1HC max largest core diameter of the insert thread [0076] P.sub.HC pitch of the insert thread

[0077] Due to the application of the above definition of the insert thread 16 as inner thread in the component opening 12, the insert thread 16 for the wire thread insert 30 may increase radially by a wire thickness of the wire thread insert 30. While the diameter of the insert thread 16 is increased for the wire thread insert 30, the pitch P.sub.HC of the insert thread 16 remains the same compared with the corresponding standard thread of a suitable screw to be received in the wire thread insert 30, which arises from the combination of insert thread 16 and wire thread insert 30.

[0078] The above formulae may be applicable in the same way for metric standard threads to be received and for inch standard threads to be received as outer thread. For this purpose, the following sizes are used in the construction of metric insert threads 16 for the nominal diameter d: [0079] d=2; 2.5; 3; 3.5; 4; 4.5; 5; 6; 7; 8; 9; 10; 11; 12; 14; 16; 18; 20 [mm].

[0080] In the construction of an inch insert thread 16, the following may be used for the nominal diameters: [0081] d=0.086; 0.099; 0.112; 0.125; 0.138; 0.164; 0.19; 0.216; 0.25; 0.3125; 0.375; 0.4375; 0.5; 0.5625; 0.625; 0.75; 0.875 [inch].

[0082] The following pitch values P may be assigned to the values for the nominal diameter d of metric outer threads to be received based on DIN13-1. [0083] P=0.45; 0.5; 0.6; 0.7; 0.75; 0.8; 1; 1.25; 1.5; 1.75; 2; 2.5; 3 [mm].

[0084] The pitch P is measured as distance between adjacent thread teeth in millimeter.

[0085] Furthermore, the flank angle α of α=60° for the values of the metric outer threads may apply.

[0086] The following pitch values P may be assigned to the values for the nominal diameter d of inch outer threads to be received, based on the Unified Thread Standard: [0087] P=0.017857; 0.020833; 0.025; 0.025; 0.03125; 0.03125; 0.041667; 0.041667; 0.05; 0.055556; 0.0625; 0.071428; 0.076923; 0.083333; 0.090909; 0.1; 0.111111 [inch].

[0088] The pitch P as distance between adjacent thread teeth is measured in inch.

[0089] Furthermore, α corresponding to α.sub.HC=60° may apply to inch outer threads.

[0090] In order to adapt the insert thread 16 to be manufactured additively to the tolerance-afflicted additive manufacturing method in a way that a metric or inch standard thread as inner thread results which may be from the combination of insert thread 16 and wire thread insert 30 in the additively manufactured component 10, such as the geometric data nominal diameter D.sub.HC, core diameter D.sub.1HC, flank angle α.sub.HC and pitch P may be adapted.

[0091] According to an embodiment of the present disclosure, adapting means that the mentioned geometric data may be each multiplied with an individual correction factor δ, δ.sub.1, δ.sub.α, δ.sub.P, in order to achieve an additive nominal diameter D.sub.AM, an additive core diameter D.sub.1AM, an additive flank angle α.sub.AM and an additive pitch P.sub.AM.

[0092] Expressed mathematically, this means may be:

D.sub.AM=D.sub.HC*δ

D.sub.1AM=D.sub.1HC*δ.sub.1

α.sub.AM=α.sub.HC*δ.sub.α

P.sub.AM=P.sub.HC*δ.sub.P

wherein δ, δ.sub.1, δ.sub.α, δ.sub.P are corresponding correction factors for the nominal diameter, the core diameter, the flank angle and the pitch.

[0093] According to the disclosure, the mentioned correction factors δ may have the following value ranges which are used for compensating tolerances when manufacturing the additive component 10:

TABLE-US-00002 correction factor value range δ 1.04-1.25 δ.sub.1 1.04-1.25 δ.sub.α 1.04-1.25 δ.sub.P 1.04-1.25

[0094] According to the disclosure, the above-mentioned tolerance adaptions may be applicable for metric threads of the size M2 to M20 and for inch threads of 2⅞ inch.

[0095] With a further increasing nominal diameter, the tolerances increase as well. Depending on the layer thickness and orientation, deviations caused by production correspond to the admitted tolerances starting from a specific nominal diameter.

[0096] According to a further alternative of the present disclosure, an additive manufacturing method of a component 10 with a component opening 12 is provided. At the inner wall 14 of the component opening 12, the insert thread 16 is provided for a wire thread insert 30 as the inner thread, instead of a standard thread for screws S (see FIG. 2).

[0097] A known additive method for manufacturing the component 10 out of plastic powder or metal powder is schematically summarized in FIG. 3. This illustration may apply similarly to the above-described manufacturing method, too.

[0098] A layer of loose powder P is provided on a construction platform (80). A laser beam L shines on the powder P with a laser power P.sub.L that is adapted to the material of the powder, in order to solidify it. The laser beam L moves with a scan speed v.sub.S over the powder layer P and shines on the portions which are determined for the solidification by the layer model of the three-dimensional component drawing. With respect to FIG. 3, solidified component portions 20 as well as portions 22 with loose or non-solidified powder arise. Amounts of loose powder 22 are arranged on the solidified portions 22 so as to solidify them by means of the laser beam and to continue to construct the component 20 layer-wise by that.

[0099] The component 10 with component opening 12 and insert thread 16 as inner thread is defined in the three-dimensional component drawing according to the following formulae:

[00007]$D_{HC}\ge d_{\mathrm{HC}\min }=D+0.75\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}$$D_{1HC}\ge d_{1\mathrm{HC}\min }=D+0.125\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}$$D_{1HC}\le d_{1\mathrm{HC}\max }=D+0.125\times \frac{P}{\tan \left(\frac{\alpha }{2}\right)}+0.373\times P-0.192\times P^{1.21}$$P_{HC}=\left(D_{\mathrm{HC}\min }-D_{1\mathrm{HC}\min }\right)\times 1.6\times \tan \left(\frac{\alpha }{2}\right)$

with [0100] d nominal diameter of the screw thread to be received in the inner thread [0101] α flank angle of the screw thread to be received in the inner thread [0102] P pitch of the screw thread to be received in the inner thread [0103] D.sub.HC nominal diameter of the insert thread [0104] D.sub.HC min smallest nominal diameter of the insert thread [0105] D.sub.1HC core diameter of the insert thread [0106] D.sub.1HC min smallest core diameter of the insert thread [0107] D.sub.1HC max largest core diameter of the insert thread [0108] P.sub.HC pitch of the insert thread

[0109] As the three-dimensional component drawing has been converted by means of known software into a layer model for the additive manufacturing, the component is additively manufactured based on this layer model. During the additive manufacturing, the laser beam L solidifies the powder P at a point of impact or impingement 24, by shining in with a specific energy per unit length E.sub.S. The energy per unit length E.sub.S is calculated from

[00008]$E_S=\frac{P_L}{V_s}$

with E.sub.S=energy per unit length of the laser, P.sub.L=laser power and v.sub.S=scan speed of the laser.

[0110] The component drawing, which is then also produced as a layer model, may define geometric areas and/or surfaces of the component 10, which face toward the incoming laser beam L and which face away from the incoming laser beam L. The regions facing toward the laser beam L are referred to as Upskin regions A.sub.up. The regions facing away from the laser beam L are referred to as Downskin regions A.sub.down.

[0111] In the area of a Downskin region A.sub.down, which is also referred to as bottom region of a projection in the component, the component 10 is constructed on loose powder. In this process, the heat which is thereby added to the powder via the laser beam is not led away via the solidified powder or material lying underneath. Rather, the heat must be led away via the powder bed or the loose powder, which has a lower heat conductive coefficient than solidified powder. Furthermore, added heat may be led away via the laterally adjacent core material of the component. As the added heat builds up more in these areas than in other areas, less energy for melting the powder is necessary. In case of unchanged energy input, the projections tend to deform. This effect may be exploited during the thread forming by processing the Downskin regions A.sub.down of the insert thread 16 with reduced energy per unit length E.sub.S compared to Upskin regions A.sub.up.

[0112] The Upskin regions A.sub.up are provided adjacent to the Downskin regions A.sub.down. This becomes obvious when constructing the insert thread 16 in the component opening 12 according to FIG. 3.

[0113] In this context, Upskin region A.sub.up refers to the upper surface of an additively manufactured component which is directed to the laser beam. The construction takes place on material that is already solidified. By that, a high heat dissipation from the melted material zone via underlying melted and already rigid powder material or core material is guaranteed. With respect to the insert thread 16, the energy per unit length when processing the Upskin regions A.sub.up may be increased to or even beyond the energy per unit length level for block-like areas 26.

[0114] In the additive manufacturing methods with adaptation of the energy per unit length E.sub.S of the laser to selected geometry areas, geometry areas with Upskin regions A.sub.up and/or with Downskin regions A.sub.down may be selected from the three-dimensional component drawing. The energy per unit length E.sub.S of the laser beam L may be reduced for selected Downskin regions A.sub.down of the insert thread 16. The reduction of the energy per unit length E.sub.S may take place compared to Upskin regions A.sub.up and/or to block-like portions 26 of the component 10 where no overhangs are present.

[0115] The energy per unit length E.sub.S of the laser beam L is determined according to E.sub.S=P.sub.L/V.sub.S (see above). In order to reduce the energy per unit length E.sub.S of the laser beam L, the laser power P.sub.L of the laser beam L may be reduced.

[0116] According to a further configuration of the present disclosure, the laser power P.sub.L for Downskin regions A.sub.down may be multiplied with a correction factor δ.sub.L. The correction factor δ.sub.L may have a value in the range from 0.7≤δ.sub.L≤0.99.

[0117] According to a further adaptation of the energy per unit length E.sub.S of the laser beam L, the scan speed v.sub.S of the laser beam L may be changed (see FIG. 3). Depending on the scan speed v.sub.S with which the laser beam L moves over the powder and applies its energy into the powder material at the point of impingement 24, the powder is solidified. When the laser beam moves faster, less energy is transmitted onto the powder than in the case when the laser would move slower.

[0118] According to different embodiments of the present disclosure, both the adaptation of the laser power P.sub.L and the adaptation of the scan speed v.sub.S of the laser beam L may be carried out alone or in combination.

[0119] Therefore, for establishing Downskin regions A.sub.down that the laser power may be adapted with the help of the above correction factor δ.sub.L. The scan speed v.sub.S of the laser beam L may be increased in addition to that.

[0120] The adaptation of the laser power P.sub.L and the scan speed v.sub.S may take place compared with the solidification of block-like portions 26 of the component 10.

[0121] As an example, the energy per unit length E.sub.S of the laser beam L with real figures is calculated according to, for example, the following equation:

[00009]$E_{S,\mathrm{down}}=\frac{P_L\times {\delta }_L}{V_s}=\frac{270\left[\mathrm{Ws}\right]\times 0.7}{0.8\left[m\right]}=236.25\left[\frac{J}{m}\right]$

[0122] The above-described additive manufacturing methods may be carried out with the help of a known laser sinter method or laser melting method with plastic powder or with metal powder.

[0123] The above-described additive manufacturing methods according to their embodiments may be combined with each other. This means that in addition to a geometric adaptation of the additively manufactured insert thread in the component, an energetic adaptation is used during manufacturing of the component to be manufactured additively.

[0124] After the additive manufacturing of the component 10 with insert thread 16, a wire thread insert 30 is screwed into the component opening 12. The combination of insert thread 16 in the additively manufactured component 10 and wire thread insert 30 screwed into it or installed in it may form a standard thread in order to screw a thread bolt into the component opening 12 with insert thread 16 and wire thread insert 30.

[0125] Accordingly, the present disclosure provides a component compound consisting of a first additively manufactured component 10 with an insert thread 16, a wire thread insert 30 installed in the insert thread 16 and a second component 40 with a through-opening 42 and a screw S connecting these two components. The screw S may have a screw head and a screw shaft, with the screw shaft extending through the through-opening 42 of the second component 40 and the thread of the screw shaft being screwed together with the first component 10 via the wire thread insert 30 that is arranged in the insert thread 16.

[0126] According to an embodiment of the present disclosure, the outer thread may comprise a nominal diameter d on the shaft of the screw and the insert thread 16 comprises a core diameter Dim according to D.sub.1HC≥d+0.46×P. For the flank angle α of the insert thread 16, an angle in the range from 80°>α>60° may be provided.