JP2010526958A - Rocker arm of internal combustion engine - Google Patents

Abstract

The invention relates to a rocker arm (1) of an internal combustion engine, wherein the rocker arm (1) can be actuated with a cam and a recess (3) provided with an inside thread is formed on a first valve-side end (2) of the rocker arm (1), an adjusting screw (4) being screwed into said recess, wherein the first valve-side end (2) of the rocker arm (1) has a U-shaped profile and the adjusting screw (4) is fixed in the recess (3) with a nut (6). In order to facilitate an actuation of the nut (6), it is provided that a space (10) is disposed inside a U-shaped profile of the first valve-side end (2) of the rocker arm (1) between a base (9) of the U-shaped profile and the nut (6).

Description

The present invention relates to a rocker arm of an internal combustion engine, the rocker arm being operable by a cam, and a notch having a female thread is formed at a first end of the rocker arm on the valve side. The adjusting screw is screwed into the notch, the first end of the rocker arm on the valve side has a U-shaped deformed portion, and the adjusting screw is fixed in the notch by the nut. It is related to the format.

BACKGROUND OF THE INVENTION Rocker arms, also called bell cranks or valve rocker arms, are used to intentionally open and close valves in internal combustion engines, such as automobile spark ignition engines. For this purpose, the cam of the camshaft acts on the cam-side end of the rocker arm, which causes the rocker arm to move at a desired time during the operation of the internal combustion engine, for example, An inflow of the fuel mixture or an outflow of combustion gas from the cylinder chamber is possible. A rocker arm manufactured by a casting method is known. This type of rocker arm may be stamped from a thin metal plate and deformed in a desired manner, particularly for weight reduction to reduce the mass to be moved when the rotational speed of the internal combustion engine is high. .

  The rocker arm has a first end on the valve side. The first end is provided with a notch. An adjusting screw is screwed into the female thread of this notch. In this case, for example, one end of the adjusting screw may be substantially hemispherical, so that it cooperates as much as possible with a correspondingly formed corresponding surface on the valve to be controlled. Can do.

  The adjustment screw is held in a desired position in the axial direction and is relative to the U-shaped profile formed by the rotating or punched and deformed metal sheet relative to the rocker arm. It is known to provide at least one nut in order to avoid turning the adjustment screw. The nut is threaded on a correspondingly formed male thread provided on the adjusting screw so that the nut directly contacts the material of the first end of the rocker arm body and locks or loosens the adjusting screw. It is tightly tightened to stop.

  U.S. Pat. No. 3,096,749 describes a rocker arm formed from two U-shaped sheet metal welded together. The first end of the rocker arm on the valve side is provided with or formed with an accommodating cylinder for accommodating an adjusting screw, which is provided with a female thread. This storage cylinder penetrates both U-shaped metal thin plates of the rocker arm. The accommodation cylinder, and thus the adjustment screw to be accommodated, is disposed between the two side walls at the first end of the rocker arm on the valve side. This rocker arm has a relatively complicated structure. This is because the rocker arm is formed of two metal sheet cutting pieces and the above-described storage cylinder.

  In the rocker arm disclosed in Japanese Patent Laid-Open No. 2001-13241, the first end portion on the valve side of the rocker arm is folded back toward itself by bending the rocker arm metal thin plate by 180 °. A material thick part is formed on the surface.

  An adjustment screw that can be brought into contact with the valve to be operated can be screwed into the threaded hole provided with the female thread in the thick part of the material. In this case, the stability of the rocker arm higher than that in the case where the metal sheet is not folded is achieved based on the above-described material thick portion.

  In U.S. Pat. No. 7,021,260, the first end of the rocker arm on the valve side is provided with a fixing opening for the adjusting screw. In this case, this first end region of the rocker arm is formed by folding the side wall of the U-shaped profile, as is apparent from FIG. 3 of US Pat. A thick part of the material is obtained at the location of the fixed opening.

  Furthermore, a valve rocker arm is known from German Offenlegungsschrift 10 388 837. In this known valve rocker arm, an adjustment screw on the valve side is arranged between the two side walls of the U-shaped first end of the rocker arm. The position of the adjusting screw is fixed in the fixing hole with the female thread by locking with two nuts or one nut with a collar or one nut with a washer. In this case, the nut is arranged on the side opposite to the side wall of the rocker arm, and therefore can only be approached with difficulty when assembled to the internal combustion engine.

  In the known rocker arm, it is extremely difficult or impossible to fix the position of the adjusting screw on the valve side or to prevent it from being loosened by at least one nut disposed between the side walls of the U-shaped profile at the first end. Is disadvantageous. This is because, for example, a tightening or loosening operation of a nut by a ring wrench or a socket wrench is actually impossible due to the side wall of the rocker arm and the narrowed assembly size.

SUMMARY OF THE INVENTION An object of the present invention is to provide a rocker arm used in an internal combustion engine, which can easily fix the position of an adjusting screw disposed between side walls with a nut.

SUMMARY OF THE INVENTION To solve this problem, in the rocker arm of the present invention, a spacer is provided between the base of the U-shaped deformed portion and the nut inside the U-shaped deformed portion of the first end on the valve side of the rocker arm. Was arranged.

  According to an advantageous embodiment of the rocker arm according to the invention, the spacer is dimensioned at least as high as the side wall of the U-shaped profile as viewed in the axial direction of the adjusting screw or of the U-shaped profile. It is dimensioned higher than the side wall.

  According to an advantageous embodiment of the rocker arm of the invention, the spacer is formed directly on the nut and has a circular or polygonal outer geometry.

  According to an advantageous embodiment of the rocker arm according to the invention, the spacer is releasably or rigidly connected to the rocker arm.

  According to an advantageous embodiment of the rocker arm of the invention, the side walls are fixed to the spacer by stamping or fixed to the spacer by molding.

  According to an advantageous embodiment of the rocker arm of the invention, the spacer is integrally formed with the first end of the rocker arm on the valve side.

  According to an advantageous embodiment of the rocker arm of the present invention, the spacer is integrated with the first end of the rocker arm on the valve side of the rocker arm in a protruding section to the base of the first end of the valve side of the rocker arm. It is formed by folding.

  According to an advantageous embodiment of the rocker arm according to the invention, a U-shaped section is cut out at the base of the U-shaped profile and is folded back towards the end on the end face side of the rocker arm. ing.

  According to an advantageous embodiment of the rocker arm according to the invention, the folded section or the folded U-shaped section is fixed in shape and / or material connection to the base of the first end of the rocker arm. Has been.

  The basis of the present invention is the recognition that in order to lock the adjusting screw of the rocker arm, at least one nut must be screwed onto the corresponding male thread of the adjusting screw and tightened. When the nut is to be screwed onto the adjusting screw on the side where the side wall of the U-shaped deformed portion at the first end of the rocker arm on the valve side is formed, the nut for fixing the position, for example, a punching / bending process It is necessary to arrange it at a distance from the base of the U-shaped profile part produced by For this purpose, additional spacers are provided. This spacer surrounds the shaft of the adjusting screw and is arranged between at least one nut and the base of the U-shaped profile.

  Accordingly, the present invention is a rocker arm for an internal combustion engine according to the features of the independent claim, wherein the rocker arm is operable by a cam and is provided with a female thread at the first end on the valve side of the rocker arm. A notch is formed, an adjusting screw is screwed into the notch, the valve end of the rocker arm on the valve side has a U-shaped deformed portion, and the adjusting screw is a nut. It is related to the type fixed in the notch by. Further, in the rocker arm of the present invention, it is proposed that a spacer is disposed between the base of the U-shaped deformed portion and the nut inside the U-shaped deformed portion at the first end of the rocker arm on the valve side. Has been.

  The advantage of the rocker arm according to the invention is that a nut is added from the base of the rocker arm profile by means of an additional spacer between the sheet metal section of the rocker arm forming the profile base and the nut screwed onto the adjusting screw. It is to be arranged at regular intervals.

  In this case, the length of the adjusting screw and / or the height of the spacer is advantageously chosen so that, for example, a ring wrench can act on the nut screwed on the adjusting screw. In this case, the side walls do not prevent this effect. Furthermore, such a spacer can be made lightweight so that the total mass to which the rocker arm is moved is only slightly increased. In the recognition of the present invention, it is self-evident that a plurality of nuts may be loosened against the adjusting screw, or a nut with a detent device may be screwed on.

  According to an improved aspect of the subject of the invention, the height of the spacer is measured at the same height as the height of the side wall as measured from the base of the U-shaped profile, or advantageously the height of the side wall. It has been proposed that it is dimensioned even higher than this, so that the nut is positioned above the side wall, so that the operation of the nut is always possible without restriction.

  According to a special embodiment of the rocker arm, it has been proposed that the spacer is formed directly on the nut and thus integrally, and has a circular or polygonal outer geometry. Therefore, an axially extended screw is used until the screw head protrudes beyond the height of the side wall of the rocker arm.

  The additional separate spacer is formed, for example, as a ring or block-like disk with a central notch and is made of a suitable material, for example hard plastic or metal. The spacer may be formed as a separate component. This component is inserted into the adjusting screw for the first time when the rocker arm is assembled, and is fixed together by a nut. It is also possible that the spacer is firmly connected to the rocker arm. A separate spacer made of metal is fixed to the rocker arm, for example by spot welding or gluing, thereby avoiding loss.

  Further, the side wall may be deformed or embossed so that a spacer made of metal or plastic is fixed at the position of the notch with respect to the adjusting screw.

  It is further proposed that an additional spacer is integrally formed with the first end of the rocker arm on the valve side. This can be done, for example, by forming the base of the deformed part at this end of the rocker arm with a length on the end face side that is greater than the length required for the rocker arm itself. This section, oriented in the longitudinal direction of the rocker arm and away from the pivot axis of the rocker arm, may subsequently be folded back in the reverse direction almost towards itself in a single machining step, so that the turn-up part is on the side wall It will be located towards itself or at the original first end of the rocker arm.

  In the recognition of the present invention, the notch provided with the female screw thread penetrates not only the base part of the deformed part but also the folded part together, whereby the adjusting screw can be introduced and fixed in position. It is self-explanatory. However, it is also possible for the female thread to be formed only on the base or only on the folded section. In this case, the hole diameter in each section without threads is set somewhat larger than the thread diameter. In this configuration, the loss of the spacer is eliminated each time.

  On the other hand, in an alternative variant, the base of the U-shaped profile is cut into a U-shape in the area of the notch and is subsequently directed to the end on the end face side of the rocker arm and close to the valve. It has been proposed that the glyph segments are folded. A drilling is then performed on this folded U-shaped section. Thus, in part, it is achieved that the nut is additionally spaced from the original base of the U-shaped profile, and the metal is obtained by stamping at the base of the profile between the side walls of the rocker arm. A sheet turn is obtained without additional material sections, so that the total weight of the rocker arm is not actually increased. Nevertheless, this makes it possible for the person skilled in the art to select, for example, the thickness and material of the rocker arm so as to have sufficient stability and strength.

  Both embodiments described above have the advantage that the folded section or the folded U-shaped section is fixed in shape and / or material connection to the base of the first end of the rocker arm. It has been. The material connection position fixing of the folded portion can be realized by spot welding, for example.

It is a figure which shows the rocker arm provided with the separate spacer. FIG. 6 shows a rocker arm with another separate spacer. It is a top view of the rocker arm provided with the separate spacer and the side wall fixed to the spacer by shaping | molding for fixing the position of this spacer. It is a figure which shows the rocker arm provided with the integrated spacer manufactured by metal thin plate folding. FIG. 6 shows another rocker arm with integrated spacers made by separate stamping and sheet metal folding.

DETAILED DESCRIPTION OF THE DRAWINGS The invention will now be described in detail by way of example with reference to the accompanying drawings.

  1 and 2 each show one rocker arm 1 in a perspective view. The rocker arm 1 can be operated in a manner known per se by a cam (not shown) arranged on the camshaft of the internal combustion engine at the second end opposite to the valve. The first end 2 on the valve side of the rocker arm 1 is formed with a notch 3 that can be seen in FIG. This notch 3 usually has a female thread. An adjustment screw 4 is screwed into the notch 3. The adjustment screw 4 has a key surface in the form of a square portion 5 for the operation tool at one end. The adjusting screw 4 can be brought into contact with the valve directly at the other end or via another adjusting member. In order to fix the position of the adjusting screw 4 to the rocker arm 1 at a desired adjusting depth or to prevent it from loosening, a nut 6 works in a manner known per se.

  The first end 2 on the valve side of the rocker arm 1 has a substantially U-shaped profile with two side walls 7 and 8 and a base 9 connecting the side walls. The entire rocker arm 1 is stamped from one piece of metal sheet at the time of its manufacture, drilled in a desired manner, and deformed.

  In order to enable tightening of the nut 6 even when the nut 6 is screwed onto the adjusting screw 4 from the side where the both side walls 7 and 8 of the U-shaped deformed portion are also arranged, one spacer 10 is additionally provided. Is provided. The spacer 10 is disposed between the nut 6 and the base 9 of the U-shaped deformed portion, and coaxially surrounds the shaft portion of the adjusting screw 4.

  In FIG. 1, the spacer 10 is formed as a separate ring, for example from hard plastic or metal. In a metal configuration, the spacer 10 can be fixed to the base 9 of the rocker arm 1 by spot welding or gluing, thereby avoiding loss of the spacer 10.

  The spacer 10 may also be formed as a substantially rectangular or square disk or block with a central notch relative to the adjustment screw 4, as shown in FIG. Such a configuration of the spacer 10 assists the coaxial orientation (positioning) between the notch of the spacer 10 and the notch 3 provided in the base 9 of the rocker arm 1 at the time of assembly.

  In both forms of the spacer 10 shown in FIGS. 1 and 2, the spacer 10 corresponds at least approximately to the height of the side walls 7, 8 as viewed in the axial direction of the adjusting screw 4, or further over the side wall height. The height of the spacer 10 is selected so that it is present.

  On the other hand, the possibility of fixing to the spacer 10 in the form of a ring here lies in the embossing or deformation of the side walls 7, 8, so that as shown in FIG. Is clamped between the side walls 7 and 8.

  Another possibility for the spacer configuration is shown in FIG. In this case, the base 9 of the U-shaped deformed portion of the first end 2 of the rocker arm 1 is formed to extend on the end face side, and is folded back toward itself by 180 °. This can be done with a processing machine known per se. In this case, the person skilled in the art can select the material thickness or a material suitable for this. Of course, the folded section 11 likewise has a notch 3 through which the adjustment screw 4 can be inserted or screwed.

  Furthermore, another embodiment is shown in FIG. In this embodiment, the base portion 9 of the first end portion 2 of the rocker arm 1 is punched into a substantially U shape in front of the end portion on the end face side and in front of the notch 3 on the rocker arm side. Subsequently, this U-shaped section 12 is also folded back by 180 ° towards itself or towards the base 9 relative to the end 2 on the end face side, and the notch 3 is processed into this double material layer, thereby The adjusting screw 4 can be screwed in. Furthermore, as shown in FIG. 5, a guide section 13 is formed at the base 9 of the rocker arm 1 in the direction of the valve. This guide section 13 serves to increase the screwing length of the adjusting screw 4.

  In both of the above-described embodiments shown in FIGS. 4 and 5, the folded sections 11 and 12 can be further fixed at the folded position by spot welding. In both of these configurations, the height of the spacer formed in this way is usually set to be smaller than the height of the side walls 7 and 8. Nevertheless, if the nut 6 is appropriately selected, the operating tool can be applied to the nut 6 at least in the section of the nut 6 extending beyond the side walls 7 and 8 when viewed in the axial direction of the adjusting screw 4.

  In order to simplify the drawing, the female threads provided in the notch 3 are not shown respectively.

DESCRIPTION OF SYMBOLS 1 Rocker arm 2 End part 3 Notch 4 Adjustment screw 5 Square part 6 Nut 7 Side wall 8 Side wall 9 Base 10 Spacer 11 Folded section 12 U-shaped section 13 Guide section

Claims (9)

  A rocker arm (1) of an internal combustion engine, the rocker arm (1) being operable by a cam, and a notch provided with a female thread on the first end (2) on the valve side of the rocker arm (1). (3) is formed, the adjusting screw (4) is screwed into the notch (3), and the first end (2) on the valve side of the rocker arm (1) is a U-shaped variant. In the type in which the adjusting screw (4) is fixed in position in the notch (3) by the nut (6), the first end (on the valve side of the rocker arm (1) ( 2. A rocker arm for an internal combustion engine, characterized in that a spacer (10) is disposed between the base (9) and the nut (6) of the U-shaped deformed portion inside the U-shaped deformed portion of 2) .   The spacer (10) is dimensioned at least as high as the side wall (7, 8) of the U-shaped profile, as viewed in the axial direction of the adjusting screw (4), or the side wall of the U-shaped profile ( 7. The rocker arm according to claim 1, which is dimensioned higher than 7,8).   Rocker arm according to claim 1 or 2, wherein the spacer (10) is formed directly on the nut (6) and has a circular or polygonal outer geometry.   The rocker arm according to claim 1 or 2, wherein the spacer (10) is releasably or rigidly connected to the rocker arm (1).   The rocker arm according to claim 1, 2, or 4, wherein the side walls (7, 8) are fixed to the spacer (10) by embossing or fixed to the spacer (10) by molding.   Rocker arm according to claim 1, 2, 4 or 5, wherein the spacer (10) is integrally formed with the first end (2) on the valve side of the rocker arm (1).   The spacer (10) is integrated with the first end (2) on the valve side of the rocker arm (1) together with the base (9) of the first end (2) on the valve side of the rocker arm (1). The rocker arm according to claim 6, wherein the rocker arm is formed by folding the protruding section (11).   A U-shaped section (12) is cut out at the base (9) of the U-shaped profile, and is folded back toward the end (2) on the end face side of the rocker arm (1). The rocker arm according to claim 6, comprising:   The folded section (11) or the folded U-shaped section (12) is connected in shape and / or material connection to the base (9) of the first end (2) of the rocker arm (1). The rocker arm according to any one of claims 6 to 8, which is fixed in position.

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