Abstract:
A throttle device in the intake section of an internal combustion engine; the throttle device including a housing part, which contains a flow cross section for an air flow. In the housing part, bearing points are provided for a throttle valve device, which can be actuated by means of an actuating drive. The actuating drive can be inserted into a receiving housing, which has first and second guide surfaces that permit the installation of the actuating drive. Fastening means are provided on the circumference surface of the receiving housing and can accommodate a closing and contacting element, which contacts electrical contacts of the actuating drive.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     In internal combustion engines, throttle devices are used in the intake tube section and can regulate the air volume required by the internal combustion engine for the combustion of fuel in the combustion chamber of the engine. As a rule, the throttle devices include a drive unit, a throttle valve supported on a shaft, and a two-part throttle housing, which can be made of cast metal or embodied as an injection molded plastic part. In addition, throttle housings are often provided with a separate housing cover, which can be used to seal the housing in order to prevent the intake of outside air. 
     2. Description of the Prior Art 
     DE 195 25 510 A1 relates to a throttle valve adjusting unit which includes a throttle valve fastened to a throttle valve shaft supported so that it can rotate in a throttle valve fitting. An actuating motor, which is supported on the throttle valve fitting and is associated with the throttle valve shaft, can move the throttle valve. This actuating motor includes at least one slider and at least one potentiometer path for detecting an adjustment position of the throttle valve shaft with an electrical connection. The actuating motor and the potentiometer are connected to the electrical connection in a connection chamber. In addition, a sealing cover closes the connection chamber. The at least one potentiometer path is affixed to the cover and the cover has a coupling part formed onto it, which is associated with the electrical connection. In addition, the cover is provided with at least one motor plug contact, which electrically contacts a reciprocal motor plug contact connected to the actuating motor when the cover is mounted onto the throttle valve fitting. 
     DE 44 01 690 A1 relates to an intake tube design, in particular for use in internal combustion engines, which includes an at least two-part shell design including a first shell part and a second shell part are connected to each other by means of an elastic seal. The first shell part has a receiving region for the seal, into which a fixing part of the second shell part reaches. The receiving region is essentially embodied as an axially extending groove formed into the wall of the first shell part. By contrast, the fixing part is embodied as an essentially axially protruding rib formed onto the wall of the second shell part. Preferably an elastic seal made of closed-pore silicone foam is used as a sealing element. According to this embodiment, the shell parts are produced as thermoplastic injection molded parts. 
     The subject of DE 198 43 771 A1 is an electromotive actuator, in particular for use in a throttle device of an internal combustion engine. The electromotive actuator includes a housing and an electric motor disposed on a drive side inside the housing. The electric motor drives a moving element disposed in the housing, in particular a throttle valve; a separate electronics housing for containing control and/or evaluation electronics can be fastened to the housing. The drive side of the electromotive actuator is connected via electrical connection means to the electronics housing; in particular, the electrical connection means are a component of the electronics housing. The throttle valve housing includes a plug connector or a socket, which is complementary to the connection of the electrical connection means. 
     OBJECT AND SUMMARY OF THE INVENTION 
     With the embodiment proposed according to the invention, a guidance of the actuating drive, which actuates a throttle device, and fastening means can be embodied directly on the throttle device housing when it is manufactured. The throttle device housing is provided with a receiving housing, which can contain an actuating drive that is preferably embodied as an electric drive unit. The receiving housing for the actuating drive can be embodied with two guide surfaces, one of which is constituted by the inside of the circumference surface of the receiving housing. Another guide surface for the actuating drive, which can be inserted into the receiving housing, can be embodied in the vicinity of a limit wall at the end of the receiving housing. 
     When the actuating drive and the receiving housing are assembled, on the one hand, a closing and contacting element can affix the actuating drive in the receiving housing; on the other hand, an electrical contacting of the actuating drive can be simultaneously achieved during insertion of the actuating drive. The closing and contacting element is provided with an electrical contact on the outside for this purpose. During installation of the closing and contacting element, it rests against contacting pins, which are provided on the end of the actuating drive, and produces an electrical connection to the plug connection provided on the closing and contacting element. The closing and contacting element can be accommodated directly on the electric drive unit and can also be embodied as a separate component that is slid onto it. 
     Fastening means can be formed on the outside of the receiving housing for the actuating drive. The fastening means, several of which can be disposed distributed along the circumference surface of the receiving housing, include openings into which protrusions embodied as detent projections on the closing and contacting element engage in snap fashion. In lieu of a detent projection connection, screws or pins can also be used to attach the closing and contacting element to the receiving housing; in this instance, the fastening means are provided with internal threads, stop surfaces, or the like. 
     Sealing elements can be accommodated in the receiving housing, which allow the closing and contacting element to protect the actuating drive from external influences, such as dust or moisture. On the other hand, a damping element can be provided between the closing and contacting element and the end of the drive unit oriented toward the closing and contacting element, thus permitting a vibrationless support of the actuating drive inside the receiving housing. 
     The seal between the receiving housing and the closing and contacting element can be produced by an integrated labyrinth seal, an inserted seal in the form of an O-ring, or a glued connection between the two components. On the other hand, the receiving housing and the closing and contacting element can be connected to each other by means of ultrasonic welding or laser welding. 
     The embodiment according to the invention presents an inexpensive fastening possibility and contacting of an actuating drive on a throttle device, which in particular limits the number of required assembly steps. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of preferred embodiments taken in conjunction with the drawings, in which: 
     FIG. 1 shows a perspective top view of a housing half of the throttle device, 
     FIG. 2 shows a perspective view of an actuating drive with an electrical contacting element, 
     FIG. 3 shows the insertion of the electrical actuating drive into a housing half of the throttle device, 
     FIGS.  4  and  4 . 1  show the actuating drive installed in a housing half of the throttle device, 
     FIG. 5 shows the course of the longitudinal section through the actuating drive contained in the housing half, 
     FIG. 5.1 shows an embodiment of a seal between the actuating drive and the receiving housing, and 
     FIG. 5.2 shows an embodiment of a damping element, which is accommodated between the actuating drive and the closing and contacting element. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1 shows a perspective top view of a housing half  2  of the throttle device which is produced by means of an original form process such as casting or by means of a multi-component injection molding technique. The housing half  2  includes a receiving shell  3  injection molded onto it, which encloses a throttle valve device, not shown here, that opens and closes an internal bore  4  of the housing half  2 . The internal bore  4  of the housing half  2  is bounded by a wall  5  and extends over a tube section  6 , i.e. the fitting region of the throttle device  1 . In the plane of a contact region  9  of the housing half  2 , a first bearing point  7  and a second bearing point  8  are formed onto the housing half  2  and rotatably support the bearing journals of a throttle valve device, not shown here, which can be inserted into the housing half  2 . The contact region  9  of the housing half  2  constitutes the support surface for the installation of an upper housing half, not shown here, whose installation fixes the throttle valve device, also not shown here, with its bearing journals in the first bearing point  7  and the second bearing point  8 . 
     In order to control the temperature of the tube section  6  of the housing half  2 , an inlet  10  and an outlet  11  are provided, through which a temperature control medium can circulate. 
     According to the depiction in FIG. 1, a receiving housing  12 , which is embodied here with a cylindrical design, is injection molded onto the side of the housing half  2 . The wall of the receiving housing  12  defines a cylindrical cavity  13  in which a first guide surface  14  is constituted by the inner wall of the receiving housing  12 . Another, or second guide surface  15  is provided in the bottom region of the cylindrically designed receiving housing  12 . The second guide surface  15  is constituted by the wall thickness of the bottom surface of the cylindrical cavity  12  through which, for example, a drive element  25  of an actuating drive  20 , which is embodied for example as a gear (see depiction according to FIG. 2) can be slid. Fastening means  16  are injection molded onto an end  17  of the receiving housing  12 . The fastening means  16  are disposed distributed, preferably, evenly, over the circumference of the cylindrically designed receiving housing  12  and permit a closing and contacting element  24  (FIG. 2) to be locked in place. 
     FIG. 2 shows a perspective view of an actuating drive  20  with electrical contacting. 
     The actuating drive  20  is embodied as a cylindrical body. The circumferential surface  21  of the actuating drive  20  is embodied with a first outer diameter  22 , while a section, which is disposed between a drive element  25  embodied as a gear and the cylindrical body of the actuating drive  20 , is embodied with a second outer diameter  23 . The outer diameter  22  of the circumference surface  21  and the second outer diameter  23  between the drive element  25  and the cylindrical body of the actuating drive  20  correspond to the inner diameters of the first guide surface  14  and the second guide surface  15  in the bottom region of the receiving housing  12 . The first and second guide surfaces  14  and  15  and the outer diameters  22  and  23  diametrically matched to them permit a precisely fitted insertion of the actuating drive  20  into the receiving housing  12  injection molded onto the housing half  2 . 
     At the end of the actuating drive  20  oriented away from the drive element  25 , a disk-shaped closure and contacting element  24  is provided. The circumference of the disk-shaped closing and contacting element  24  is provided with protrusions  26 , which can engage in detent fashion, for example, with the fastening means  16  shown in FIG. 1 on the circumference of the receiving housing  12 . On the inside of the closing and contacting element  24 , contacting elements  27  and  28  are provided, which can connect the actuating drive  20  to an electrical connection  31  when the actuating drive  20  is inserted into the cavity  13  of the receiving housing  12  and the closing and contacting element  24  is subsequently fastened to the fastening means  16  of the receiving housing  12 . 
     In FIG. 3, the actuating drive  20  is inserted in the insertion direction  30  into the cavity  13  of the receiving housing  12 . The circumference surface  21 , embodied with the first diameter  22 , is used as an insertion surface along the first guide surface  14 , i.e. the inside of the circumference surface of the receiving housing  12 . The closing and contacting element  24  can be integrated into the actuating drive  20 , i.e. injection molded onto it, or can be slid onto it afterward, before the actuating drive  20  is inserted in the insertion direction  30  into the cavity  13  of the receiving housing  12 . The protrusions  26  embodied on the circumference surface of the closing and contacting element  24  engage in detent fashion in the fastening means  16  on the receiving housing  12  (see depiction according to FIG.  4 . 1 ). 
     FIGS.  4  and  4 . 1  show the actuating drive installed in a housing half of the throttle device, with the actuating drive  20  completely enclosed by the receiving housing  12 . The closing and contacting element  24  detent-connected to the fastening means  16  on the circumference surface of the receiving housing  12  hermetically seals the actuating drive  20  in the receiving housing  12  off from the outside. 
     FIG. 4.1 shows an enlargement of an assembly point  31  between the receiving housing and the closing and contacting element  24 , with the fastening means  16  on the circumference of the receiving housing  12  is embodied as a detent connection. To that end, in their region disposed in the mounting direction  30 , the protrusions  26  injection molded onto the closing and contacting element  24  are provided with an oblique surface  33 . The oblique surface  33  of the protrusions  26  travels into openings  34  of the fastening means  16 , which include a bridge-shaped section, and after being completely inserted into them, produces a snap connection, which can also be released again. 
     The fastening means  16  according to the depiction in FIG. 4.1 are produced by means of material bridges  16  made of injection molded plastic. If the fastening means  16  are penetrated by detent projections  32 , it is not necessary to provide an internal thread in the vicinity of the openings  34  of the fastening means  16 . By contrast, if the closing and contacting element  24  is fastened to the fastening means  16  on the circumference of the receiving housing  12  by means of a screw connection, then the insides of the openings  34  of the fastening means  16  can be provided with threaded sections. 
     As shown in FIG. 5, the actuating drive  20  is contained inside the receiving housing  12 ; the contacting element is detent connected to the fastening means  16  at assembly points  31 . The sectional course identified as A—A in FIG. 5 is shown in FIG. 5.1. The depiction according to FIG. 5.1 shows an embodiment of a seal between the actuating drive and the receiving housing. 
     The actuating drive  20  is contained inside the receiving housing  12  and its circumferential surface  21  rests with a first outer diameter  22  against the first guide surface  14  of the receiving housing  12 . The section embodied with the second outer diameter  23  on the actuating drive  20  rests against the second guide surface  15  inside the receiving housing  12 . The receiving shell  3  that is injection molded together with the receiving housing  12  encloses the drive element  25  configured as a gear, which is driven by means of the actuating drive  20 . The driving element  25  embodied as a gear is supported on a drive shaft  29 . 
     In the depiction according to FIG. 5.1, a sealing element, which is embodied as an O-ring  47  and is inserted between the closing and contacting element  24  and the end  17  of the receiving housing  12 , protects the actuating drive  20  contained inside the receiving housing  12  from moisture and the penetration of dirt particles. In lieu of an insertable seal in the form of an O-ring  47 , the closing and contacting element  24 , which is embodied in the form of an injection molded disk, can encompass the end with an overlap  42  so that the seal can be integrated directly into the closing and contacting element  24 . The collar embodied on the closing and contacting element  24  can be fastened to the circumferential surface of the receiving housing, for example by means of a materially adhesive process for example of a thermal joining process such as ultrasonic welding or laser welding. It is also possible to glue the collar on the closing and contacting element  24  to the circumference surface of the receiving housing  12 . On the side of the closing and contacting element  24  opposite from the contacts  27  and  28 , an electrical connection  41  is provided, by means of which a voltage can be applied to the actuating drive  20  inside the receiving housing  12 . 
     The depiction according to FIG. 5.2 shows an embodiment of the integration of an actuating drive into the inside of a receiving housing; the actuating drive is supported in a vibrationless manner by means of a damping element  44  contained between a first support surface  45  on the actuating drive  20  and the inside of the closing and contacting element  24 , which functions as a second support surface  46 . The damping element  44  can be made of elastomer material, embodied in the form of a ring, and inserted into the annular space  43  (see depiction according to FIG.  5 . 1 ). The mounting of the closing and contacting element  24  onto the receiving housing  12 , whether by means of a detent connection, a screw connection, ultrasonic welding, laser welding, or gluing, exerts an initial tension on the damping element  44  contained inside the receiving housing  12  so that the actuating drive  20 , guided on the first guide surface  14  and on the second guide surface  15 , is supported in a vibrationless manner. The longer the overlap  42  of the collar of the closing and contacting element  24  can be embodied in relation to the circumference surface of the receiving housing  12 , clearly the better a seal is produced against the penetration of moisture and dirt particles. 
     The receiving housing  12  according to the invention, which is injection molded onto a housing half  2  of a throttle device  1 , with first and second guide surfaces  14  and  15  embodied on it, permits a simple and inexpensively produced installation of an actuating drive  20  into it. When the actuating drive  20  is locked in place in the cavity  13  of the receiving housing  12 , the actuating drive  20  is automatically and immediately contacted electrically so that the only remaining step is to electrically connect the electrical connection  41  of the closing and contacting element  24 . The assembled unit, i.e. the housing half  2  with the actuating drive  20  contained in it, can be produced at a significantly lower cost, eliminating a large number of installation and processing steps, particularly if the housing half  2  with the receiving housing  12  injection molded onto it can be manufactured by means of an original forming process such as casting or plastic injection molding. In plastic injection molding, it is particularly advantageous to manufacture the housing half  2  of the throttle device  1  using two-component injection molding. 
     The foregoing relates to preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims.