MXPA97000264A - Motion accessory of mo - Google Patents

Abstract

The present invention relates to a control arrangement for an accessory unit of an internal combustion engine, said accessory unit has a control shaft arranged in axial alignment with an arrow operated by the engine and having an end face disposed opposite to an end face of said arrow operated by the motor, said arrow by the motor is supported by a friction bearing to which a lubricant and a coupling carrier disposed between said end faces is provided for coupling said arrow operated by the motor with the said of control, said coupling carrier includes a pin projecting eccentrically in an axial direction of the end face of said arrow operated by the motor and a carrier mounted on said control arrow and having a carrier structure which engages said pin and a lubricant collecting space placed in communication with the friction bearing lubricant that leaks from the cushion friction ete for the lubrication of the coupling carrier

Description

ENGINE CONTROL ACCESSORY BACKGROUND OF THE INVENTION The invention relates to an accessory control unit for an internal combustion engine wherein the accessory unit has a control shaft arranged in axial alignment with an arrow driven by the engine and is moved by means of an impeller coupling. . DE 23 26 684 A1 discloses an internal combustion engine with a camshaft and an accessory unit with an arrow which is coaxially positioned with the camshaft and which is engaged to rotate with the cam shaft by means of a coupling mounted on the arrow of the accessory unit and connected to the camshaft. However, this arrangement has the disadvantage that the vibrations of the camshaft are transmitted directly to the accessory unit. As a result, sensitive accessory units are subject to greater wear. It is the object of the present invention to provide a control for an accessory motor unit which is simple and reduces the transmission of vibrations from the camshaft to the accessory unit.

SUMMARY OF THE INVENTION In an accessory control arrangement of an internal combustion engine, wherein the accessory unit is mounted on the motor in such a way that its control shaft is placed in axial alignment with an arrow driven by the motor and coupled to it by means of a coupling structure, the coupling structure includes a bolt projected axially and eccentrically from the front face to the end of the driving shaft of the engine and which couples with a carrier mounted on the control shaft of the accessory unit. The arrangement according to the invention is very simple in its design, and consequently, it is simple to install. Also, the transmission of vibrations from the camshaft to the arrow of the accessory unit is eliminated or at least greatly reduced. In a preferred embodiment, wherein the driven shaft of the motor is supported by a friction bearing, lubricant leaking from the bearing is picked up and used to lubricate the coupling whereby wear is essentially eliminated. The additional modalities and advantages thereof will be apparent from the following description of the invention based on the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view of a part of the crankcase of an internal combustion engine with an accessory control unit mounted thereon and connected to a camshaft by means of a coupling arrangement; Figure 2 shows the coupling arrangement of Figure 1, Figure 3 shows the arrangement of Figure 1 with a different lubricant supply arrangement; and Figure 4 shows the coupling arrangement of Figure 3. DESCRIPTION OF THE PREFERRED MODALITIES The figures show a part of the crankcase 1 of an internal combustion engine including a camshaft 2 shown partially with a cam 3, the shaft of cams 2 being supported at its end by a bearing 4 disposed in the crankcase 1. For supplying lubricant to the bearing surface 5, the crankcase 1 includes a hole 6 for lubricant. An accessory control unit, generally designated by the number 7, has a control arrow 8 positioned coaxially with the camshaft 2, it is mounted on the crankcase, for example by means of a flange 14. The control arrow 8 is driven by the camshaft by means of a coupling carrier 9. The coupling carrier 9 comprises a carrier 10 which is firmly mounted on the control shaft 8 for rotating therewith and a pin 12 mounted eccentrically on the front end of the camshaft 2. The carrier 10 comprises a body 12 similar to a disc with a rod 17 that extends out radially. The transition area between the disk-like body 16 and the rod 17 are shaped to form a cradle 18 where the pin 12 is coupled to the carrier 10 during rotation of the camshaft 2. The function, the type, and the design of the accessory unit is not important with respect to the present invention and therefore is only briefly described. The embodiment of Figure 1 shows a fuel pump in which the control arrow 8 is rotated at the same speed as the camshaft 2 of the internal combustion engine by means of the coupling carrier 9. At the opposite end of the control arrow 8, the current pump unit 13 is mounted on the control arrow 8 to rotate it with the mass so that the fuel pump is operated at the speed of the camshaft 2. In the area of the coupling carrier 9, the crankcase 1 and the housing 14 of the accessory control unit 7 include cavities forming a lubricant collecting space. The lubricant collecting space 15 must be large enough so that the circular movement of the pin 12 and the carrier is not impeded. The collecting space 15 serves to collect the leaked lubricant leaking from the bearing at the front end 11 of the camshaft 2. In order to prevent the lubricant from escaping from the collecting space in an uncontrolled manner, the housing 14 of the unit 8 accessory is sealed in relation to the crankcase 1 and in relation to the accessory unit 8. The leaked lubricant is collected in a sump 19 at the bottom of the collecting space. With each rotation of the camshaft, the pin 12 and the carrier 10 are sprinkled by the sump 19 so that the coupling carrier 9 in the area of the cradle 18 will always be sufficiently lubricated. Lubrication is necessary in order to avoid wear on the pin 12 and the carrier 10, respectively, in the area 18 of the cradle due to the relative movements of these parts 12, 10 which are caused by the vibrations of the camshaft 2. In order to prevent the entire collecting space 15 from being filled with lubricant, an overflow 20 may be provided within the housing 14 of the accessory unit 7 as indicated in Figures 1 and 2. The overflow consists of a duct 21 which it branches into the side of the storage space 15 and extends to the bottom of the housing 14 and of a hole 22 connecting the duct 21 with the crankcase 1. By selecting the level at which the duct 21 branches off from space 15 collector, the volume of the sump can be determined. Preferably, the overflow 20 is arranged at a level such that it ensures sufficient lubrication in the coupling carrier 9 but not at a high level. A large volume of unnecessary lubricant in the collector space 15 would lead to energy loss due to the undesirable friction loss from increased splashing. In addition to the disposition of the overflow 20 in the housing 14 as shown in the embodiment of Figures 1 and 2, it is possible to place the conduit 21 as well as the hole 22 in the casing 1. Furthermore, it is possible to provide the collecting space 15. exclusively from a cavity that is provided either in the crankcase 1 or in the housing 14 of the accessory unit 7. The course of the duct 21 and the orifice 22 is preferably selected so that the lubricant in excess of the storage space 15 returns back to the crankcase 1 only by gravity. Another embodiment for the lubrication of the coupling carrier 9 is shown in Figures 3 and 4, where identical parts are designated by the same reference numerals as used in Figures 1 and 2. In this embodiment, the overflow 20 and the conduit 21 are eliminated. In this case, the collector space is in communication with the interior 24 of the crankcase of the internal combustion engine by means of a through hole 23 extending through the front end of the crankcase 2. Preferably the through hole 23 is displaced of the location of the bolt 12, by 180 °. The through hole 23 is a lubricant inlet and also a lubricant discharge conduit. When the internal combustion engine is at rest, the lubricant is drained from the collecting space 15 into the space 24 of the crankcase to the lower edge of the through hole 23. Consequently, when the engine is not running, the level of the lubricant remaining in the collecting space depends on the angular position of the camshaft 2 and, together with it, the orifice 23. During operation of the engine, the lubricant can enter the collecting space 15 through the hole 6 for lubricant and / or through hole 23. However, the lubricant can also leave the storage space 15 through the passage orifice 23 and flow into the crankcase 24 of the engine. As a result, during operation of the engine, a balance is established between the lubricant inlet flow and the lubricant outlet flow, whereby a lubricant level is established where the through hole is completely submerged in the sump 19 of the lubricant. lubricant when it is in a lower position as shown in Figure 3. This arrangement has the advantage that, when starting the engine, the collecting space is filled with lubriciously faster than with the first mode. The invention of course is not limited to a coupling carrier between the control arrow 8 of an accessory control unit 7 and a camshaft 2 of an internal combustion engine. Said coupling arrangement can of course also be provided for coupling an accessory unit to the crankcase or to another engine drive component. The storage of the lubricant leaking from a friction bearing in a collecting space is used as a lubricant sump and the disposition of an overflow for the return of the excess lubricant to the original lubricant circulation system can be used not only for the coupling carrier shown herein, but may be used in connection with a friction bearing for the lubrication of areas that could otherwise be subjected to frictional wear.

Claims (7)

1. A control arrangement for an accessory unit of an internal combustion engine, said accessory unit has a control shaft arranged in axial alignment with an arrow operated by the engine and having an end surface disposed opposite an end surface of said operated arrow by the motor, and a coupling carrier disposed between said end faces for coupling said arrow operated by the motor with said control shaft, said coupling carrier includes a pin projecting eccentrically in an axial direction of the surface of said motor. end of said arrow operated by the motor and a carrier mounted on said control shaft and having a carrier structure that engages said pin. A control arrangement according to claim 1, wherein said carrier is in the form of a disc with a rod projecting radially outwardly extending from said disc so that a transition area similar to a cradle is formed wherein, therefore, said pin is received during the rotation of said arrow operated by the motor. 3. A control arrangement according to claim 1, wherein said arrow operated by the motor is supported by a friction bearing to which a lubricant is supplied and wherein a collecting space is provided in which the lubricant that is Leakage from said friction bearing is collected and used for the lubrication of said coupling carrier. 4. A control arrangement according to claim 3, wherein said collection space is provided with an overflow by means of which the excess lubricant is returned from said collecting space to the engine lubrication system. A control arrangement according to claim 1, wherein the end of said arrow driven by the motor is supported by a friction bearing in the crankcase of said motor and said crankcase has a lubricant intake hole to admit lubricant in said friction bearing and wherein said lubricant collecting space is located in the area of said coupling carrier as a cavity formed in at least one of said crankcase and said accessory unit. A control arrangement according to claim 1, wherein the end of said arrow operated by the motor is supported on the crankcase of said motor by a friction bearing and wherein said lubricant collecting space is a cavity formed by at least one of the housings of the accessory unit and said casing wherein also a portion of said carrier coupling is located and said arrow operated by the engine includes a through hole extending between said collector space and the casing of said unit. Internal combustion engine. 7. A control arrangement according to claim 6, wherein said through hole is angularly displaced with respect to said pin by 180 °.