WO2006042773A1

WO2006042773A1 - Throttle device

Info

Publication number: WO2006042773A1
Application number: PCT/EP2005/054460
Authority: WO
Inventors: Ralf Kromer; Stefan Emmert; Robert Peichl
Original assignee: Robert Bosch Gmbh
Priority date: 2004-10-19
Filing date: 2005-09-08
Publication date: 2006-04-27
Also published as: DE102004050791A1; BRPI0513234A; JP2008517196A

Abstract

In throttle devices for controlling an internal combustion engine, the throttle valve must be mounted in a precise manner. The invention relates to a throttle device comprising a throttle valve housing (2), wherein a locking element holds the throttle valve shaft (6) in the axial direction. Said throttle device is especially suitable for vehicles having a throttle internal combustion engine.

Description

throttling device

State of the art

The invention relates to a throttle device for an internal combustion engine according to the preamble of claim 1.

Throttle devices for internal combustion engines usually have a throttle valve shaft which is mounted so as to be pivotable in a throttle valve housing and on which a throttle valve is formed or fastened. Through the throttle body, a gas channel runs. For example, air or a fuel-air mixture can flow through the gas channel to an internal combustion engine. By pivoting the throttle shaft, the throttle opens or closes the gas passage.

In order that the throttle valve does not abut the wall of the gas passage, it is known to closely tolerate the mobility of the throttle shaft in its axial direction.

In the throttle device shown in the published patent application DE 39 24 611 Al, the throttle valve shaft in the axial direction, i. in the longitudinal direction of the throttle shaft, fixed by a transverse by the throttle shaft pin.

In the throttle device shown in DE 30 48 995 Al, the axial force transmission between the throttle shaft and the throttle body takes place via a built-in throttle body in the ball bearing. In the German patent application DE 195 10 622 Al a bearing means is pressed into the throttle body against which a spring biases the throttle shaft, for the purpose of exact axial positioning of the throttle shaft.

Depending on the material used, in particular depending on the material used for the throttle body, it may happen in the prior art that shifts the axial bearing of the throttle shaft, so that the undisturbed mobility of the throttle in the throttle body is no longer guaranteed at each temperature.

Advantages of the invention

The throttle device according to the invention for an internal combustion engine having the characterizing features of claim 1 has the advantage that with the help of the blocking element, the throttle shaft can be fixed in the axial direction excellent. Because the locking member provides for the axial bearing of the throttle shaft, which can be the throttle shaft in radial

Direction leading bearings are designed to be very simple and you do not have to worry that act on this the throttle shaft in the radial direction bearing bearing in the axial direction acting forces. Even if the bearing bearing in the radial direction with very little pressure in the throttle body is installed, no unwanted axial displacement of this bearing must be feared. This allows in a particularly simple manner, the use of plastic for the throttle body with particularly good durability.

In addition, the blocking element can also be designed so that stabilization of the throttle body is achieved in the region of the bearing guiding the throttle valve shaft in the radial direction. This is particularly favorable if the throttle body or an extension provided on the throttle body, in which the radial bearing is located, consists of plastic.

The measures listed in the dependent claims advantageous refinements and improvements of the throttle device according to claim 1 are possible. If the blocking element is designed such that it encompasses a projection provided on the throttle body, this gives the advantage that the blocking element can be attached to the throttle body housing in a particularly simple manner.

By providing the disc engaging the throttle valve shaft or the disc holding the throttle valve shaft in the axial direction, the advantage is obtained that the throttle valve shaft can be manufactured very simply and yet the throttle valve shaft can be axially fixed very easily in both directions.

The acting between the locking element and the throttle body barrier has the advantage that the locking element can be connected very easily with little effort to the throttle body, but accidental redetachment is avoided by the throttle body.

drawing

Preferably selected, particularly advantageous embodiments of the invention are shown in simplified form in the drawing and explained in more detail in the following description. 1 shows a plan view of a selected exemplary embodiment of the throttle device, FIG. 2 shows a longitudinal section in the region of the circle marked II in FIG. 1, FIG. 3 shows a longitudinal section in the region of the circle marked II in FIG. 1 with modified details 4 shows a longitudinal section in the region of the circle marked II in FIG. 1 with further modified details, and FIGS. 5A and 5B show a blocking element in longitudinal section and in plan view.

Description of the embodiments

The throttle device according to the invention can be used in various internal combustion engines, in which with the aid of a throttle flap is to be controlled by a gas duct. The gas channel is provided, for example, for a flow of an air, a fuel-air mixture, etc. Depending on the swivel position of the throttle valve, the flow of the gas is more or less throttled. Normally, the throttle valve can be swiveled up to 90 °. But there is - A -

also embodiments in which the throttle flap can be pivoted by less than 90 ° or more than 90 °, for example up to 180 °. The throttle shaft with the throttle may be pivoted by means of an actuator acting on the throttle shaft. The adjusting device is, for example, a servomotor which acts on the throttle valve shaft and adjusts the throttle valve shaft, for example directly or via a transmission.

1 shows a plan view of a first, preferably selected, particularly advantageous embodiment of the throttle device.

1 shows the throttle device with a throttle body 2. Through the throttle valve housing 2 runs in Figure 1 in frontal view shown gas channel 4. The gas channel 4 is for example a leading to combustion chambers of an internal combustion engine intake manifold. Transversely through the gas channel 4 extends in the throttle body 2 pivotally mounted throttle shaft 6. At the throttle shaft 6, a throttle valve 8 is attached. The throttle valve 8 may for example also be made in one piece with the throttle valve shaft 6 made of plastic.

At the throttle body 2, there is a gear box 9 and an adjusting device 18. The adjusting device 18 includes, for example, an electric servomotor. This servo motor can act on the throttle shaft 6 via a transmission present in the gearbox 9 and pivot it in the circumferential direction. The throttle shaft 6 is rotatably supported on one side of the gas channel 4 via a first bearing 24 (FIG. 2) and on the other side of the gas channel 4 via a second bearing in the throttle body 2.

In FIG. 1, a circle marked II is shown with a dashed line. Figure 2 shows a longitudinal section along the axis of the throttle shaft 6 through the throttle body 2 in the region of the circle IL shown in Figure 1. Figure 2 shows the longitudinal section through the throttle body 2 in the region in which the throttle shaft 6 via the bearing 24 in the Throttle body 2 is mounted. In all figures, identical or equivalent parts are provided with the same reference numerals. Unless otherwise stated or shown in the drawing, that applies with reference to one of the figures mentioned and illustrated also in the other embodiments. Unless otherwise stated in the explanations, the details of the various embodiments can be combined with one another.

As FIG. 2 shows, there is a stepped bore 10a introduced into the throttle body 2. A portion of this stepped bore 10a serves as a bearing seat 10 for the bearing 24 for supporting the throttle shaft 6 in the throttle body 2.

To the throttle body 2 of the preferred embodiment selected for receiving the bearing 24, an extension 22 is formed. The throttle body 2 with the extension 22 has a substantially cylindrical circumference 2a in the region of the bearing space 10. The periphery 2a forms an outer periphery outside the bearing 24. In the selected embodiment, the extension 22 (FIG. 2) projects into the gear box 9 (FIG. 1).

In the preferred embodiment selected, the radial guide bearing 24 is a sliding bearing in the form of an inserted socket. But the bearing 24 may also be a rolling bearing, for example with balls or rollers or needles as rolling elements. However, the bearing 24 may also be integrally formed integrally with the throttle body 2; that is, the throttle shaft 6 may be performed radially without bushing directly in the throttle body 2.

On the circumference 2a or outer periphery of the extension 22 of the throttle body 2, a locking element 20 is attached.

The blocking element 20 is preferably cylindrical or sleeve-shaped and has approximately the shape of a stepped, frontally open, sleeve-shaped cylinder with a cylinder region 20a and a radial region 20b. The blocking element 20 is preferably closed in the circumferential direction. However, the blocking element 20 can also be slotted, for example, along a surface line.

The blocking element 20 consists for example of metal, preferably of a hardened metal, in particular spring steel. If the blocking element 20 is at least partially slotted along a surface line, then a particularly good spring action results, which depending on the tolerance position can facilitate the attachment of the blocking element 20 to the throttle body 2. If the locking element 20 is closed in the circumferential direction, then one obtains a particularly good stabilizing effect of the material of the throttle body 2. Because the throttle body 2 is preferably made of plastic, the locking element 20 can easily on underside against the circumference 2a on the throttle body. 2 be plugged.

At the periphery of the throttle shaft 6, there is a circumferential groove 6b. In the recess 6b a disc 26 is installed. The disc 26 has an inner diameter that is smaller than the outer diameter of the throttle shaft 6. For installing the disc 26 in the recess 6b, the disc 26 is slotted in the radial direction. The disk 26 is roughly C-shaped.

The disc 26 has an outer diameter which is at least slightly larger than the inner diameter of the bearing 24. However, it is proposed to select the outer diameter of the disc 26 larger than the diameter of the bearing seat 10. The inner diameter of the radial portion 20b of the locking member 20 is smaller than the outer diameter the disc 26.

The attached to the extension 22 and at least indirectly to the throttle body 2 Sperr¬ element 20 presses with its radial portion 20b radially outside of the bearing 24, the disc 26 in the axial direction against the throttle body 2, more precisely, in the embodiment against the end face of the extension 22nd ,

The groove 6b on the throttle shaft 6 is slightly wider than the thickness of the disc 26th

Because the locking member 20, the disc 26 is fixed in the axial direction against the throttle body 2 and because the disc 26 engages in the recess 6 b, the position of the throttle shaft 6 in axial Direction excellent and with little play positioned. The blocking element 20 is pressed with pretension on the circumference 2a of the throttle body 2 and thereby securely fixed.

Since the disc 26 is slightly thinner than the groove 6b is wide, the throttle shaft 6 can be easily rotated with a small torque, although the disc 26 is held by the locking member 20 on the throttle body 2.

The throttle shaft 6 rotates relative to the disc 26. The throttle shaft 6 and the disc 26 are preferably made of rather hard, low-wear material, so that in the proposed embodiment with a good durability is expected.

FIG. 3 shows by way of example a modification of the throttle device in the region which is marked with the circle II in FIG. FIG. 3 shows, on the basis of a further, preferably selected exemplary embodiment, a longitudinal section through the throttle body 2 in the region in which the throttle shaft 6 is mounted in the throttle body 2 via the bearing 24.

As FIG. 3 shows, it has an axially protruding step 28 concentric with the bearing space 10. As a result, there is a gap 30 between an end face of the extension 22 of the throttle body 2 and the end face of the radial area 20b of the blocking element 20 facing the throttle body 2.

In this embodiment, the disc 26 is fixed on the throttle shaft 6. The gap 30 is greater in the radial direction than the outer diameter of the disc 26 and in the axial direction, d. H. in the longitudinal direction of the throttle shaft 6, the gap 30 is slightly wider than the thickness of the disc 26. This allows the disc 26 within the

Space 30 together with the throttle shaft 6 rotate freely. Because the gap 30 of the throttle body 2 on the one hand and on the other hand by the radial portion 20b of the locking member 20 is precisely limited, the throttle valve shaft 6 is guided by means of the locking member 20 in cooperation with the disc 26 in the axial direction precisely. Because the disc 26 is slightly thinner than the gap 30 in the longitudinal direction, the throttle shaft 6 with small torque can be easily rotated, although the disc 26 is held on the throttle shaft 6.

In the particularly advantageous embodiments illustrated in FIGS. 2 and 3, the one blocking element 20 can prevent deflection of the throttle valve shaft 6 in both longitudinal directions of the throttle valve shaft 6.

FIG. 4 shows a further modification in the region of the longitudinal section along the axis of the throttle valve shaft 6 in the region within the circle marked II in FIG.

In the embodiment shown in Figure 4, the throttle shaft 6 has a frontal shoulder 6c.

The inner diameter of the radial region 20b of the blocking element 20 is smaller than the larger diameter of the throttle valve shaft 6. As a result, the blocking element 20 ensures that the throttle valve shaft 6 can not move unintentionally to the right (relative to FIG. 4). A guide of the throttle shaft 6 axially to the left (with respect to Figure 4) is ensured by a further, not shown in Figure 4 axial guidance.

Because the blocking element 20 indirectly positions and guides the throttle shaft 6 in the axial direction via the disk 26 (FIGS. 2 and 3) or directly, without the bearing 24 being loaded with the axial guidance of the throttle valve shaft 6, the bearing 24 be very simple or the bearing 24 can be installed with little preload or virtually no bias in the Drosselklappen¬ housing 2. This greatly facilitates the use of plastic for the throttle body 2.

As shown in the embodiments shown in Figures 2 to 4, the blocking element 20 and the bearing 24 act independently of each other. This means that the axial guidance of the throttle valve shaft 6 is independent of the radial guidance of the throttle valve shaft 6. The blocking element 20 can be pressed onto the circumference 2 a with prestressing. As a result, the blocking element 20 can serve as stiffening of the bearing receptacle 10 in the region of the bearing 24. This results in an improved durability even if the material of the Drosselklappen¬ housing 2 and the extension 22 is a relatively soft plastic, and even if the extension 22 in the region of the bearing 24 is quite thin-walled.

FIGS. 5A and 5B show the blocking element 20 as an individual part before it is attached to the throttle valve housing 2. FIG. 5A shows a section of a longitudinal section through the blocking element 20. FIG. 5B shows a plan view of the blocking element 20 with the viewing direction marked by the arrow V in FIG. 5A.

In the proposed throttle device, there is a lock 32. The lock 32 acts between the throttle body 2 and the lock member 20.

In the preferred selected embodiments, the lock 32 is formed by the fact that on the cylinder portion 20a of the locking member 20, a tab 32a is formed. Roughly speaking, the tab 32a is a piece of the cylinder portion 20a of the locking member 20 punched out on three sides. The free end of the tab 32a is slightly bent inward in the radial direction. At the free end of the tab 32a, a pointed claw 32b is provided. At the free end of the tab 32a and a plurality of pointed claws 32b may be provided.

The inner diameter of the cylinder portion 20a of the locking member 20 is approximately equal to the circumference 2a of the throttle body 2 or about smaller than the circumference 2a of the throttle body 2, so that the locking element 20 can be plugged or pressed onto the extension 22 with little effort. The tab 32a of the lock 32 is pressed radially outward. Because the material of the locking element 20 elastically springs, the claw 32b of the lock 32 presses against the material of the throttle body 2. Because the material of the throttle body 2 is preferably relatively soft, the lock 32 gets caught in the throttle body 2. This ensures that the Locking element 20 can not accidentally slip off the throttle body 2 and the extension 22 or slip back. The barrier 32 together with the radial region 20 b ensure that the blocking element 20 is permanently fixed in all directions relative to the throttle body 2.

Claims

claims

1. Throttle device for an internal combustion engine, with a throttle body (2) and with a throttle shaft (6) with a throttle valve (8), wherein the throttle shaft (6) provided in the throttle body (2) Lageraufhahme (10) in the throttle body (2) pivotally mounted and with the aid of an on the throttle shaft (6) engaging actuating device (18) is pivotable, characterized in that at least indirectly to the throttle body (2) fixed, at least a part of the throttle body (2) embracing locking element (20) has a mobility the throttle shaft (6) limited in an axial direction.

2. Throttle device according to claim 1, characterized in that the blocking element (20) on one of the throttle body (2) provided substantially cylindrical circumference (2 a) at least partially surrounds.

3. Throttle device according to claim 1, characterized in that on the throttle body (2) an extension (22) is formed and the locking element (20) on the extension (22) is attached.

4. Throttle device according to claim 3, characterized in that the extension (22) has a substantially cylindrical circumference (2a) and the blocking element (20) at least partially surrounds the circumference (2a) of the extension (22).

5. Throttle device according to one of the preceding claims, characterized in that the throttle valve shaft (6) in the axial direction at least indirectly on a radial region (20b) of the locking element (20) is guided.

6. Throttle device according to claim 5, characterized in that the radial region (20b) of the blocking element (20) via a disc (26), the throttle valve shaft (6) leads in the axial direction.

7. throttle device according to claim 6, characterized in that the blocking element (20) the disc (26) in the axial direction at least indirectly against the throttle body (2) acted upon.

8. throttle device according to claim 6, characterized in that the disc (26) relative to the blocking element (20) is movable in the circumferential direction.

9. throttle device according to one of the preceding claims, characterized in that a barrier (32) prevents accidental displacement of the blocking element (20).

10. Throttle device according to one of the preceding claims, characterized in that the blocking element (20) is sleeve-shaped.

11. Throttle device according to one of the preceding claims, characterized in that the blocking element (20), the throttle valve shaft (6) leads in the axial direction, regardless of a bearing of the throttle valve shaft (6) in the radial direction.