Bonding fixture

Abstract

The invention relates to a joining clamp for joining a plate encoder wheel on a camshaft tube, having: - a first jaw part and a second jaw part, which are translationally adjustable towards one another, wherein on each jaw part at least two support rollers for the plate encoder wheel are arranged, - an extrusion post arranged on the first jaw part, which can extrude a first stop of the plate encoder wheel and thus enable the plate encoder wheel to be twisted in the joining clamp about an axis, - a jaw part stop arranged on the first jaw part or on the second jaw part, against which the plate encoder wheel is oriented with angular accuracy by means of a rotational movement caused by the extrusion post using a second stop. As a result, a weight-optimized plate encoder wheel can be joined on a camshaft tube very precisely, quickly and energy-efficiently.

Description

Technical Field

[0001] This invention relates to a coupling jig for engaging a sheet metal coding wheel onto a camshaft tube, and a coupling device having such a coupling jig. Furthermore, this invention relates to a method for engaging a sheet metal coding wheel onto a camshaft tube. Additionally, this invention relates to a camshaft having a camshaft tube and a sheet metal coding wheel engaged thereon using the method according to the invention and when using the coupling device according to the invention. Background Technology

[0002] The camshaft used in an internal combustion engine has an encoder wheel fastened to the camshaft tube. During engine operation, the encoder wheel interacts with a corresponding sensor, generating a definite signal in the sensor. This signal enables the engine control unit to determine the precise angular position of the camshaft. This is particularly necessary for controlling the intake and / or exhaust valves.

[0003] In conventional camshafts, the cam and, for example, the encoder wheel are joined to the camshaft tube via a thermal fit. For this purpose, the cam or encoder wheel is heated and / or the camshaft tube is cooled before engagement. The heated encoder wheel expands about its inner diameter, while the cooled camshaft tube contracts about its diameter. As the encoder wheel moves onto the camshaft tube, both ensure a strong engagement. However, this approach is disadvantageous because heating the encoder wheel and / or cooling the camshaft tube requires specific temperature-regulating times, and establishing a thermal fit requires specific holding times. This generally results in longer cycle times and therefore higher costs. Furthermore, due to unfavorable tolerance ranges, excessive overlap can sometimes occur, which in turn leads to difficulties in engaging the encoder wheel onto the camshaft tube.

[0004] Furthermore, the coding wheels used to date are typically constructed as sintered components, which not only have a relatively high weight but also require an incalculable period of time for thermal bonding.

[0005] Furthermore, for the camshaft in an internal combustion engine to function perfectly, the encoder wheel must be precisely positioned at a predetermined angle. This can also present difficulties in the thermal bonding of the sintering wheel, as it must be precisely held in the predetermined angular position during temperature compensation. This is achieved through appropriate bonding fixtures. Summary of the Invention

[0006] Therefore, the problem to be solved by the present invention is to describe a coupling clamp that can at least partially overcome the disadvantages known from the prior art.

[0007] According to the present invention, this problem is solved by the following.

[0008] This invention is based on the common concept of constructing a clamping fixture for engaging sheet metal encoder wheels onto a camshaft tube of a camshaft, thereby enabling not only simple and quick clamping but also simple and highly precise orientation of the sheet metal encoder wheel. Sintered wheels have been commonly used to date, which are significantly heavier and require relatively long heating times for thermal bonding. Using sheet metal encoder wheels (e.g., with a material thickness between 1 mm and 3 mm, preferably 2 mm) provides a particularly lightweight encoder wheel, which can be engaged solely by press fitting, thus eliminating the energy-intensive and therefore expensive thermal bonding process with significantly longer cycle times. The clamping fixture according to the invention has a first clamp and a second clamp, which are translatably adjustable toward or away from each other, wherein at least two support rollers for the sheet metal encoder wheel to be engaged are arranged on each clamp. Here, a particularly adjustable pressing post is arranged on the first clamp, which presses a first stop on the sheet metal encoder wheel for orientation, thereby allowing the sheet metal encoder wheel to be twisted within the clamping fixture via the support rollers. Here, the torsion of the sheet metal encoder wheel, achieved by the extrusion column, is realized around the axis of the sheet metal encoder wheel, which corresponds to the axis of the camshaft tube after the engagement process. Furthermore, clamp stops are arranged on the first clamp and / or the second clamp, and the sheet metal encoder wheel abuts against the clamp stops by the second stops through the rotational movement caused by the extrusion column, thereby achieving precise angular orientation. Therefore, using the engagement fixture according to the invention, it is possible to precisely and quickly engage a weight-optimized sheet metal encoder wheel as a signal encoder wheel onto the camshaft tube, regardless of whether a thermal fit or a press fit at room temperature is used for this purpose.

[0009] The sheet metal encoder wheel used for this purpose has a central opening with a bent inner edge, through which a press-fit or heat-fit connection is achieved with the outer peripheral side of the camshaft tube. Here, the inner edge is bent at 90° relative to the sheet metal encoder wheel. Signal tongues, bent in the same direction, are arranged on the outer periphery of the sheet metal encoder wheel. These signal tongues transmit corresponding signals to a sensor, which can then determine the precise rotation angle position of the camshaft and transmit it to the engine control unit. Thus, the engine control unit of the internal combustion engine can, for example, operate the phase adjuster used to adjust the camshaft. This sheet metal encoder wheel can be relatively easily constructed as a sheet metal stamping, and is not only significantly lighter than encoder wheels made of, for example, sintered materials, but also allows for significantly faster engagement, especially when using press fitting, i.e., engagement by simple press-fitting onto the camshaft tube.

[0010] In a particularly preferred embodiment of the engagement clamp according to the invention, the first clamp and / or the second clamp have concave inner contours. Here, the support rollers in the respective clamps of the engagement clamp enable the plate encoder wheel to rotate relative to the engagement clamp, and thereby enable the orientation of the plate encoder wheel in its angular position. Here, the concave inner contours of the first and / or second clamps can be constructed complementary to the outer contour of the signal tongue plate of the plate encoder wheel, wherein contact between the plate encoder wheel and the clamps of the engagement clamp is typically achieved only via support rollers or pressing posts and a first stop, a clamp stop, and a second stop.

[0011] In an advantageous improvement of the engagement clamp according to the invention, the extrusion column can be adjusted hydraulically, electrically, by means of a spring, or pneumatically. Here, pneumatic and electrical adjustment of the extrusion column enables rapid and highly precise adjustment, without requiring, for example, hydraulic fluid, which is significantly more difficult to handle in terms of environment. Alternatively, the extrusion column can be screwed into or otherwise fixedly connected to the first clamp, thereby automatically achieving precise orientation of the rotation angle of the sheet metal coding wheel in the engagement clamp without the need for separate adjustment of the extrusion column relative to the first clamp when both clamps move together.

[0012] Furthermore, the present invention is based on the general concept of equipping the joining device with the joining clamp described in the preceding paragraphs, wherein the joining device additionally includes a slider for clamping and moving the camshaft tube into the sheet metal encoder wheel clamped by the joining clamp. With the joining device according to the invention, the sheet metal encoder wheel to be joined can thus be easily and quickly clamped and precisely oriented in its predetermined angular position, so that the camshaft tube guided by the slider can be easily moved or pressed through the opening of the sheet metal encoder wheel.

[0013] In an advantageous improvement of the engagement device according to the invention, a first stop ring is provided to fix the plate encoder wheel when the camshaft is moved into the plate encoder wheel, and a second stop ring can be used alternatively. Here, the first stop ring can have a smaller supporting surface for the plate encoder wheel because, in this case, the plate encoder wheel surrounds the first stop ring with its signal tongue and its inner ring. Therefore, for example, an optimized arrangement of the required structural space in the axial direction on the camshaft tube can also be achieved. Thus, the first stop ring is designed to be embedded in the plate encoder wheel in the axial direction, i.e., in the direction of movement of the camshaft tube, to fix the plate encoder wheel to be engaged. In contrast, the second stop ring provides a larger supporting surface and is used if the signal tongue of the plate encoder wheel points opposite to the engagement direction of the camshaft tube. Here, the first and second stop rings can provide axial support for the plate encoder wheel when the camshaft tube is moved into the opening of the plate encoder wheel.

[0014] Furthermore, the present invention is based on the general concept of describing a method for engaging a sheet metal encoder wheel onto a camshaft tube of a camshaft, wherein the sheet metal encoder wheel is clamped by an engagement jig as described in the preceding paragraphs, and clamped between its two jaws. For this purpose, the two jaws are first separated, and then the engagement jig is guided onto the sheet metal encoder wheel to be clamped. Subsequently, the two jaws move toward each other, clamping the sheet metal encoder wheel between them via its support rollers. Then, or here, the clamping pin of the engagement jig presses against the first stop of the clamped sheet metal encoder wheel, causing the sheet metal encoder wheel to twist within the engagement jig until the sheet metal encoder wheel abuts against the jaw stop of the first or second jaw using its second stop, and thereby precisely oriented at a predetermined angle. Subsequently, the camshaft tube is moved through the sheet metal encoder wheel, and thereby the sheet metal encoder wheel is engaged onto the camshaft tube. Therefore, by using the method according to the invention, a simple, rapid, and highly precise engagement of the sheet metal encoder wheel onto the camshaft tube can be achieved.

[0015] In an advantageous improvement to the method according to the invention, the sheet metal encoder wheel is engaged onto the camshaft tube by a thermal fit. For this purpose, it is possible, for example, to cool the camshaft tube and / or heat the sheet metal encoder wheel, wherein the sheet metal encoder wheel can be heated, for example, to a temperature between 30°C and 150°C. Alternatively, it is also conceivable to fix the sheet metal encoder wheel onto the camshaft tube by a press fit, thereby achieving a further reduction in cycle time and complete elimination of the energy consumption for thermal fitting. Due to customer requirements, the sheet metal encoder wheel can transmit torque, but is not required to transmit torque, and can subsequently generate a signal only through its external signal transmission section or signal tongue; for this purpose, a significantly reduced press fit compared to a cam is sufficient.

[0016] In a particularly preferred embodiment of the method according to the invention, a first stop ring is used whenever the signal tongue of the sheet metal encoder wheel points in the engagement direction of the camshaft tube. Alternatively, a second stop ring is used whenever the signal tongue (signal transmitting section) of the sheet metal encoder wheel points in the opposite direction to the engagement direction of the camshaft tube. Here, the signal tongue or signal transmitting section is always oriented in the same direction as the inner ring of the sheet metal encoder wheel in order to keep the axial thickness of the sheet metal encoder wheel as low as possible. Here, the first stop ring has a smaller support surface than the second stop ring and is embedded in the sheet metal encoder wheel between the outer signal tongue and the inner ring during engagement.

[0017] Furthermore, the present invention is based on the general concept of describing a camshaft having a camshaft tube and a plate encoder wheel engaged thereon using the method and engagement device according to the preceding paragraph. Such a camshaft can be provided with significantly reduced energy consumption and significantly faster cycle time, thereby also being provided at a particularly lower cost.

[0018] Other important features and advantages of the invention will become apparent from the accompanying drawings and related figures.

[0019] It should be understood that, without departing from the scope of the invention, the features described above and will still be set forth below may be used not only in the combinations described separately, but also in other combinations or individually. A superior unit, such as a separately indicated device, apparatus, or arrangement of the aforementioned and hereafter named components, may form a separate element or component of the unit, or a region or section of the unit as a whole, even if this is not shown differently in the accompanying drawings. Attached Figure Description

[0020] Preferred embodiments of the invention are shown in the accompanying drawings and are described in detail in the following description, wherein the same reference numerals refer to the same or similar or functionally identical parts. Hereinafter, they are illustrated schematically. Figure 1 A view of the engagement clamp according to the invention is shown. Figure 2 A front view of the sheet metal encoder wheel engaged with the camshaft tube is shown. Figure 3 An oblique view of the sheet metal coding wheel is shown. Figure 4 A cross-sectional view of the engagement device is shown, which has no engagement clamps but has a first stop ring. Figure 5 As shown in Figure 4 The illustration shows a second stop ring. Figure 6 A side view is shown of a camshaft manufactured according to the method of the invention and using the engagement jig of the invention. Detailed Implementation

[0021] according to Figure 1 According to the invention, a coupling jig 1 for engaging the sheet metal coding wheel 2 onto the camshaft tube 3 of the camshaft 4 (see...) Figure 6The clamp has a first clamp 5 and a second clamp 6, which can be translated, adjusted to be closer to or further apart from each other in direction 7. Each clamp 5, 6 is provided with two support rollers 8 for supporting and fixing the sheet metal coding wheel 2. Furthermore, a particularly adjustable pressing post 9 is provided on the first clamp 5, which can be adjusted, for example, hydraulically, by means of a spring, pneumatically, or electrically. Alternatively, it is obviously conceivable that the pressing post 9 can be adjusted by a threaded connection, but is fixedly connected to the first clamp 5 during normal use. The pressing post 9 either presses the first stop 10 of the sheet metal coding wheel 2 when activated alone, thereby causing the sheet metal coding wheel to twist in the engaging clamp 1 via the support rollers 8, or it twists when both clamps 5, 6 move together, as long as the pressing post 9 fixedly connected to the first clamp 5 is involved.

[0022] Furthermore, on the first clamp 5 or the second clamp 6, according to Figure 1 A clamp stop 11 is arranged on the first clamp 5. The plate coding wheel 2 abuts against the clamp stop by the second stop 12 through the rotational movement caused by the extrusion column, and is precisely oriented at this angle.

[0023] The first clamp 5 or the second clamp 6 has a concave inner contour, which enables particularly effective clamping of the plate coding wheel 2. It is even theoretically conceivable that the plate coding wheel 2 can be form-fitted onto the concave inner contour of the first clamp 5 and / or the second clamp 6.

[0024] As mentioned, the extrusion column 9 can be adjusted hydraulically, electrically, mechanically, or by means of a spring or pneumatic mechanism. It is also conceivable that the extrusion column is screwed into the first clamp 5 and locked by a lock nut (Kontomutter), so that when the two clamps 5 and 6 move together, the extrusion column 9 is not adjusted separately relative to the first clamp 5, so that the rotation angle of the plate coding wheel 2 in the engagement fixture 1 is accurately oriented automatically.

[0025] If observe Figure 2 and Figure 3 Therein, one can see the sheet metal encoder wheel 2, which has an inner ring 13 and an outer signal transmitting section or signal tongue 14. This sheet metal encoder wheel 2 can be constructed as an inexpensive and easily manufactured sheet metal stamping, and has a wall thickness between 1 mm and 3 mm, preferably 2 mm. With this implementation, it is much lighter than, for example, encoder wheels made of sintered metal, and furthermore, requires significantly less energy in its manufacture.

[0026] If observe Figure 4 and Figure 5 There you can see the joining device 15 according to the invention, which has according to Figure 1The engagement jig 1 (not shown) and the slider 16 for clamping and moving the camshaft tube 3 into the plate encoder wheel 2 clamped by the engagement jig 1.

[0027] Here, according to Figure 4 The first stop ring 17 is installed in the engagement device 15, and according to Figure 5 A second stop ring 18 is used. Here, when the camshaft tube 3 moves into the center opening of the plate encoder wheel 2 in the axial direction, two stop rings 17 and 18 can be used to fix the plate encoder wheel 2.

[0028] If observe Figure 4 As can be seen, the first stop ring 17 is embedded in the space defined in the radial direction between the inner ring 13 and the signal tongue plate 14, wherein, in this case, the first stop ring 17 must adapt to the internal space between the inner ring 13 and the outer signal tongue plate 14 in its radial extension. The first stop ring 17 is used here only if the signal tongue plate 14 of the plate encoder wheel 2 points along the engagement direction 19 of the camshaft tube 3. Conversely, according to... Figure 5 The second stop ring 18 is used only when the signal tongue 14 of the plate encoder wheel 2 and the engagement direction 19 of the camshaft tube 3 are opposite. The support surface 20 of the second stop ring 18 is larger than the support surface 19 of the first stop ring 17 because the second stop ring 18 does not need to be embedded in the space defined by the signal tongue 14 and the inner ring 13.

[0029] The plate coding wheel 2 is engaged with the camshaft tube 3 of the camshaft 4 according to the method of the present invention described below: First, the sheet metal coding wheel 2 is clamped by the engagement jig 1, and here it is held between its two clamps 5 and 6. Here, the compression post 9 compresses the first stop 10 of the clamped sheet metal coding wheel 2, and causes the sheet metal coding wheel to move around in the engagement jig 1 according to... Figure 1 The axis 21, perpendicular to the plane of the paper, is twisted until the plate coding wheel abuts against the clamp stop 11 of the first clamp 5 or the second clamp 6 (in the first clamp 5) using its second stop 12, and thereby occupies a precisely predetermined angular position. Subsequently, the camshaft tube 3 is moved, for example, by being squeezed through the plate coding wheel 2.

[0030] Here, the plate encoder wheel 2 can be fixed to the camshaft tube 3 by thermal bonding, wherein alternatively, a pure press fit at room temperature is also conceivable, since the plate encoder wheel 2 is mainly used to generate signals.

[0031] Here, according to Figure 6The diagram shows a camshaft 4 and a plate encoder wheel 2 joined thereto by means of the method according to the invention. Here, a drive plug 22 is also shown on the longitudinal end side of the camshaft tube 3, which must also occupy a predefined position relative to the camshaft tube 3 in terms of rotational angle. For this purpose, for example, a mark 24 can be arranged on the camshaft tube 3 (see...). Figure 2 Here, a signal is generated by the sheet metal encoding wheel 2 via the corresponding signal edge 23, which restricts the signal tongue plate 14 in the peripheral direction. Here, the sheet metal encoding wheel 2 rests against the support roller 8 via its signal tongue plate 14.

[0032] In the longitudinal direction, support portions 26 are provided between the respective supports 25 for, for example, a sheet metal encoder wheel 2 or a cam (not shown) (see...). Figure 6 Compared to the remaining camshaft 4, the support portion is reduced in its outer diameter by, for example, 0.05 mm to 0.1 mm, so that the engagement of the sheet metal encoder wheel 2 on the camshaft tube 3 does not cause scratching of the support portion 26.

[0033] Therefore, using the joining jig 1 according to the invention, the joining device 15 according to the invention, and the method according to the invention, a sheet metal encoder wheel 2 that can be manufactured inexpensively and with optimized weight can be joined very precisely to the camshaft tube 3 of the camshaft 4. Compared to encoder wheels constructed of sintered metal to date, the sheet metal encoder wheel 2 can also be joined selectively using thermal bonding or energy-saving press bonding.

Claims

1. A coupling fixture (1) for engaging a sheet metal coding wheel (2) onto a camshaft tube (3), the coupling fixture having: - First clamp (5) and second clamp (6), the first clamp and the second clamp can be adjusted to move towards each other, wherein, At least two support rollers (8) for the plate coding wheel (2) are arranged on each clamp (5, 6). - A pressing post (9) arranged on the first clamp (5) can press the first stop (10) of the plate coding wheel (2) and thus allow the plate coding wheel to twist about the axis (21) in the engagement clamp (1). - A clamp stop (11) is arranged on the first clamp (5) or the second clamp (6), and the plate coding wheel (2) is abutted against the clamp stop by the second stop (12) by the rotational movement caused by the extrusion column and thus precisely oriented at an angle.

2. The joining clamp according to claim 1, Its features are, The first clamp (5) and / or the second clamp (6) have concave inner contours.

3. The engagement clamp according to claim 1 or 2, Its features are, - The compression column (9) can be adjusted hydraulically, by means of a spring, electrically or pneumatically relative to the first clamp (5), or - The extrusion column (9) is fixedly connected to the first clamp (5) and can only be adjusted together with the first clamp.

4. The engagement clamp according to claim 3, Its features are, The extrusion column (9) is threadedly connected to the first clamp (5).

5. A coupling device (15) having a coupling clamp (1) according to any one of claims 1 to 4 and a slider (16) for clamping and moving the camshaft tube (3) into a plate encoder wheel (2) clamped by the coupling clamp (1).

6. The joining device according to claim 5, Its features are, A first stop ring (17) is provided to fix the plate encoder wheel (2) when the camshaft tube (3) is moved into the plate encoder wheel (2), and a second stop ring (18) may be used therein.

7. A method for engaging a sheet metal coding wheel (2) onto a camshaft tube (3), wherein, - The plate coding wheel (2) is clamped by the engagement clamp (1), and is hereby clamped between the two clamps (5, 6) of the engagement clamp. - The pressing column (9) presses against the first stop (10) of the clamped plate coding wheel (2) and twists the plate coding wheel in the engagement clamp (1) until the plate coding wheel abuts against the clamp stop (11) of the first clamp (5) or the second clamp (6) by means of its second stop (12), and thereby oriented at a predetermined angle. - Move the camshaft tube (3) through the plate coding wheel (2).

8. The method according to claim 7, Its features are, The plate coding wheel (2) is fixed to the camshaft tube (3) by thermal bonding.

9. The method according to claim 7 or 8, Its features are, The plate coding wheel (2) is fixed on the camshaft tube (3) by press fitting.

10. The method according to claim 7 or 8, Its features are, - The first stop ring (17) is used as long as the signal tongue (14) of the plate encoder wheel (2) is pointing in the engagement direction (19) of the camshaft tube (3), and / or - The second stop ring (18) is used as long as the signal tongue (14) of the plate encoder wheel (2) points in the opposite direction to the engagement direction (19) of the camshaft tube (3).

11. A camshaft (4), the camshaft having a camshaft tube (3) and a sheet metal coding wheel (2), characterized in that, The sheet metal coding wheel (2) is engaged on the camshaft tube (3) by means of any one of claims 7 to 10 and by the engagement device (15) according to claim 5 or 6, wherein the sheet metal coding wheel (2) has a first stop (10) and a second stop (12), wherein the first stop (10) is configured to be squeezed by the extrusion post (9) of the engagement device (15) when the sheet metal coding wheel (2) is engaged on the camshaft tube (3) and thus to cause the sheet metal coding wheel to rotate about the axis (21) in the engagement jig (1), and the second stop (12) is configured to abut against the clamp stop of the engagement jig by rotational movement caused by the extrusion post when the sheet metal coding wheel (2) is engaged on the camshaft tube (3) and thereby be precisely oriented at an angle.

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