DEVICE FOR FILLING AND REMOVING A LUBRICANT AT A HOUSING

Abstract

A filling and draining device for filling lubricant into and draining lubricant out of a housing (1), having a lubricant line (2, 21, 22) through which the lubricant passes into the housing (1), during filling, and through which the lubricant passes when the lubricant is drained from the housing (1). The housing (1) has a valve (6) through which the lubricant flows during filling and draining such that, for filling, the valve (6) adopts a first aperture width for the lubricant and, for draining, the valve (6) adopts a second aperture width for the lubricant.

Claims

1-10. (canceled)

11. A filling and draining device for filling and draining a lubricant into or from a housing (1), the filling and draining device comprising: a lubricant line (2, 21, 22) through which, during filling, the lubricant flows into the housing (1), and, during draining, the lubricant flows out of the housing (1), a valve (6) through which the lubricant flows during filling and draining, and the valve (6) adopts a first aperture width for the lubricant for filling and the valve adopts a second aperture width for the lubricant for draining.

12. The filling and draining device according to claim 11, wherein the valve (6) has a valve element (62) which is arranged in the valve (6) in such a manner that due to the flow of the lubricant and depending on flow direction, the valve element (62) either moves into contact with a first stop (63) where the valve element produces the first aperture width, or moves into contact with a second stop (64) where the valve element produces the second aperture width.

13. The filling and draining device according to claim 11, wherein the valve (6) is arranged inside the lubricant line (2, 21, 22).

14. The filling and draining device according to claim 12, wherein the lubricant line (2) comprises a first partial line (21) and a second partial line (22), the valve (6) has a valve chamber (61), the valve element (62) is arranged and axially movable in the valve chamber (61) and the first and the second partial lines (21, 22) open into the valve chamber (61) at opposite ends of the valve chamber (61), one of the first and the second stops (63, 64) for the valve element (62) are arranged, in each case, at outlets of the first and the second partial lines (21, 22) into the valve chamber (61), when the valve element (62) rests against the first stop (63), the first aperture width is formed between the first stop (63) and the valve element (62), and when the valve element (62) rests against the second stop (64), the second aperture width is formed between the second stop (64) and the valve element (62).

15. The filling and draining device according to claim 11, wherein the valve (6) is arranged inside the housing (1).

16. The filling and draining device according to claim 15, wherein the valve (6) is arranged inside a wall of the housing (1).

17. A transmission housing (1) with a housing area for arranging a power take-off (PTO) on the transmission housing (1), and with a lubricant line (2, 21, 22) for supplying the power take-off (PTO) with a lubricant from the transmission housing (1) and for filling the transmission housing (1) with the lubricant, a filling and draining device comprising the lubricant line (2, 21, 22) through which, during filling, the lubricant flows into the housing (1), and, during draining, the lubricant flows out of the housing (1), and a valve (6) through which the lubricant flows during filling and draining, the valve (6) adopts a first aperture width for the lubricant for filling and the valve adopts a second aperture width for the lubricant for draining.

18. The transmission housing (1) according to claim 17, wherein the transmission housing has a connection (3) of the lubricant line (2, 21, 22) for the power take-off (PTO) in the housing area provided for arranging the PTO.

19. The transmission housing (1) according to claim 17, wherein the lubricant line (2, 21, 22) is a main pressure line.

20. A method of producing a transmission with a power take-off (PTO) and with the transmission housing (1) according to claim 17, the method comprising at least: arranging the power take-off (PTO) on the transmission housing (1) in such a manner that a lubricant line of the power take-off (PTO) is coupled with the lubricant line (2, 21, 22) of the filling and draining device of the transmission housing (1) so that, during operation of the power take-off (PTO), the lubricant is drawn from the transmission housing (1), via the lubricant line (2, 21, 22), into the power take-off (PTO), and during operation of the power take-off (PTO) the valve (6) adopts the second aperture width.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Below, the invention is explained in greater detail with reference to figures from which further preferred embodiments of the invention emerge. The figures show, in each case schematically:

[0033] FIG. 1: A section through a transmission housing according to the prior art,

[0034] FIG. 2: A proposed valve for a filling and draining device for the transmission housing of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] In the figures, the same or at least functionally equivalent components and elements are denoted by identical indexes.

[0036] FIG. 1 shows a section through a transmission housing 1 of a motor vehicle known as such. Through the transmission housing 1 there extends a lubricant line 2 in the form of a duct arranged inside the wall of the transmission housing 1.

[0037] Outside the transmission housing 1 the lubricant line 2 opens into a connection 3 for a PTO that can be arranged on the transmission housing 1. Thus, on the transmission housing 1 in the area of the exterior outlet of the lubricant line 2 an area of the housing is provided for arranging the PTO on the transmission housing 1, for example an appropriately shaped flange and threaded bores for fixing the PTO. In this part of the housing there is also, in particular, an opening such as a housing window through which the PTO can extend into the transmission housing 1 and through which drive power can be tapped off from the transmission housing 1 for the PTO. In FIG. 1 the connection 3 is sealed by a closure since no PTO is arranged on the transmission housing 1 at the time.

[0038] Inside the transmission housing 1 the lubricant line 2 opens into a bore of an intermediate plate 4. On the intermediate plate 4 a lubricant pump 5 is attached. This pump 5 serves to deliver the lubricant present inside the transmission housing 1also through the lubricant line 2, when a PTO is connected thereto. The lubricant line 2 is connected directly to the pump 5. If necessary the pump 5 can have a pressure regulating valve for adjusting the pump pressure. Accordingly, inside the lubricant line 2 there is a particular and if needs be a regulated main pressure of the lubricant system. Thus, the lubricant line 2 is a main pressure line.

[0039] For example, the lubricant line 2 has two partial lines 21, 22. These are arranged at an angle to one another so that the fitting space available is used optimally. Moreover, in that way the outlets of the lubricant line 2 are positioned at the necessary places.

[0040] In the present case the lubricant line 2 serves not only for draining lubricant out of the housing 1 when a PTO is connected thereto, but also for at least partially filling the housing 1 with the lubricant. Thus, the lubricant line 2 with its connection 3 form a filling and draining device for filling and draining the lubricant into and out of the housing 1.

[0041] During filling, the lubricant is passed into the inside of the housing via the connection 3 and the lubricant line 2. Conversely, during draining the lubricant passes out of the housing through the lubricant line 2 and the connection 3. During the draining process the return flow of the lubricant back into the transmission housing 1 takes place at other points, for example through the PTO. Thus, there are two possible flow directions for the lubricant through the lubricant line 2. In FIG. 1 these flow directions are indicated by oppositely directed arrows.

[0042] During filling a relatively large volume flow of lubricant is needed in order to keep the filling time short. In contrast, during draining a relatively smaller volume flow of lubricant is required in order to prevent unnecessary and possibly damaging oversupply of the PTO with lubricant. This can be done after filling by positioning an extra diaphragm in the lubricant line 2 or the connection 3. However, this represents an additional process step and thus a potential source of error.

[0043] Accordingly it is proposed to provide a valve for the lubricant in the filling and draining device shown in FIG. 1, which valve produces different aperture widths depending on the flow direction of the lubricant. Thus, automatically and without further process steps different volumes flows and/or pressures are obtained, on the one hand during filling and on the other hand during draining.

[0044] FIG. 2 shows as an example a possible design of such a valve 6. The valve 6 is arranged inside the lubricant line 2 in the area circled in FIG. 1. The valve 6 has a valve chamber 61 into which the two partial lines open. In FIG. 2 the outlet of the partial line 21 is at the left-hand end of the valve chamber 61 and the outlet of the partial line 22 is at the right-hand end of the valve chamber 61. Specifically, the partial line 21 opens axially into the valve chamber 61. Specifically, the partial line 22 opens laterally into the valve chamber 61. Thus, there are different angles between the longitudinal axes of the valve chamber 61 and the respective longitudinal axes of the partial lines 21, 22.

[0045] Inside the valve chamber 61 there is provided (exactly) one valve element 62. The valve element 62 is for example in the form of a metal ball. The valve element 62 can be moved axially within the valve chamber 61 by the flow of lubricant. That is indicated by the double-arrow shown in FIG. 2. At the outlets of the partial lines 21, 22 stops 63, 64 are provided for the valve element 62. Depending on the flow direction, the valve element 62 will rest against the stops 63, 64. Thus, during filling the valve element 62 rests against the stop 63 (on the left), which corresponds to a first valve position. And during draining the valve element 62 rests against the stop 64 (on the right), which corresponds to a second valve position. The valve element 62 against the (left-hand) stop 63 is represented by a broken line, whereas the same valve element 62 against the (right-hand) stop 64 is represented by a continuous line.

[0046] The stops 63, 64 and/or the valve element 62 are designed such that a free space (for example a gap) always remains between the stop 63, 64 and the valve element 62 for the lubricant to flow past the valve element 62 when the valve element 62 is up against the stop. Thus, a certain volume flow of lubricant can flow past the valve element 62 and through the lubricant line 2. The free space remaining at each stop 63, 64 forms the aperture width of the valve 6 in its respective valve position. The free spaces at the stops 63, 64 and hence the aperture widths of the valve 6 in its two valve positions are different from one another. Consequently, depending on the flow direction the valve 6 automatically provides different aperture widths on the one hand while the transmission housing 1 is being filled with lubricant, and on the other hand while lubricant is being drained out of the transmission housing 1.

[0047] The filling of the transmission housing 1 with lubricant through the lubricant line 2 can be carried out at some other place and by some other person or organization than the fixing of the PTO to the transmission housing 1. For example the filling takes place at a transmission manufacturer, particularly toward an end of the production process there. Then the transmission is transported to a purchaser. Only there is the PTO arranged on the transmission, so completing the actual production of the transmission. For that, in a production step carried out by the purchaser the PTO is fitted onto the transmission housing 1. During this, on the one hand elements of the PTO are coupled to the transmission in order to tap off drive power. On the other hand, a lubricant line of the PTO for lubricating the PTO is coupled to the lubricant line 2 of the filling and draining device in the transmission housing 1. For example this is done by coupling the connection 3 shown in FIG. 1 to the lubricant line of the PTO. As a result, when the PTO is operating the lubricant passes from the transmission housing 1 by way of the lubricant line 2 and the valve 6 (see FIG. 2) to the PTO, and during this the valve 6 adopts the smaller aperture width. Consequently it is ensured that during its operation (i.e. while it is receiving lubricant from the transmission housing 1) the PTO is only supplied with a necessary, reduced volume flow of lubricant, instead of the large volume flow required during filling.

[0048] A corresponding process can also be carried out by a refurbisher of a used transmission, on which no PTO was previously arranged, but which is in principle suitable for it. Thus, by virtue of the above-described retrofitted arrangement of a PTO on the transmission, the transmission is enabled to carry out new tasks for which it is again fully equipped.

INDEXES

[0049] 1 Housing, transmission housing [0050] 2 Lubricant line [0051] 21 Partial line [0052] 22 Partial line [0053] 3 Connection [0054] 4 Intermediate plate [0055] 5 Lubricant pump [0056] 6 Valve [0057] 61 Valve chamber [0058] 62 Valve element [0059] 63 Stop [0060] 64 Stop