[001] This invention relates to a washer / dryer wherein it is achieved that the vapor originating in the tub is prevented from reaching the detergent box. [002] In washers / dryers, the water that is utilized as heated during the washing process evaporates and reaches the detergent box via the hose between the detergent box and the tub, which is used to supply detergent to the tank. The water vapor that reaches the detergent box causes the powder detergent inside the detergent box to become humid and stick to the internal surfaces of the detergent box. Some part of the detergent that sticks to the surface may not be removed by the water transferred from the interior of the detergent box to the tub and so remains inside the detergent box. For that reason, detergent inside the detergent box can not be utilized efficiently and moreover, the probability that the detergent box gets choked during the following operations as a result of an accumulation of detergent increases. [003] In one of the applications in the current state of the art, in the International Patent Application WO 03/022121, a description is given of a baffle placed between the detergent dosing unit and the tub. [004] The aim of the present invention is the realization of a washer / dryer wherein means are provided to prevent the vapor originating in the tub from reaching the detergent box. [005] The washer / dryer designed to fulfill the objectives of the present invention is il¬ lustrated in the attached figures where: [006] Fig.l - is a schematic representation of a washer / dryer. [007] Fig.2 - is a perspective view of a detergent box comprising a baffle. [008] Fig.3 - is an exploded view of a detergent box comprising a baffle. [009] Fig.4 - is a perspective view of a baffle comprising two opposite pins at its movement axis. [010] Fig.5 - is a perspective view of a baffle comprising a pin housing at its movement axis. [011] Fig.6 - is a perspective view of a frame. [012] Fig.7 - is a perspective view of a baffle and a frame. [013] Fig.8 - is a side view of a baffle attached to a frame wherein the flow is blocked. [014] Fig.9 - is a side view of a baffle attached to a frame wherein the flow is enabled. [015] Fig.10 - is a schematic representation of a baffle attached to a frame and also to a detergent box wherein the flow is blocked. [016] Fig.l 1 - is a schematic side view of a baffle attached to a frame and also to a detergent box wherein the flow is enabled. [017] Fig.12 - is a schematic side view of a baffle which is placed by being attached to a frame and also to a detergent box, and incorporates a first and a second part that are positioned at the same plane, wherein the flow is blocked. [018] Fig.13 - is a schematic side view of a baffle which is placed by being attached to a frame and also to a detergent box, and incorporates a first and a second part that are positioned at different planes, wherein the flow is blocked. [019] Elements shown in figures are numbered as follows: [020] 1. Washer / dryer [021] 2. Detergent box [022] 3. Baffle [023] 4. Frame [024] 5. Hose [025] 6,16. Pin [026] 7,17,27. Pin housing [027] 8. Tub [028] 9. Stop [029] 10,20. Cap [030] The washer / dryer (1) comprises a tub (8) in which the laundry is washed / dried, a detergent box (2) which holds the detergent necessary to wash the laundry, a hose (5) connecting the detergent box (2) and the tub (8), a baffle (3) closes the communication between the detergent box (2) and the tub (8), positioned at the outlet of the detergent box (2), preventing the water vapor inside the tub (8) from leaking into the detergent box (2) while allowing the flow of the detergent inside the detergent box (2) into the tub (8), rotating around a movement axis (A) which connects two points on one side or on opposite sides of the said baffle (3) and separates the said baffle (3) into two parts (Y, Z) and, one or more than one stop (9) which is used to hold the baffle (3) at a desired position by limiting its motion. [031] In the application of the present invention, as the fluids such as detergent etc. start to flow from the detergent box (2), the path blocked by the baffle (3) that is held leaning against the stop (9) opens as a result of the rotation of the second part (Z) towards the tub (8) and the rotation of the first part (Y) towards the detergent box (2), around the movement axis (A). As the motion of the said fluids stops, the path just opened is blocked back by means of the baffle (3) as a result of the rotation of the second part (Z) towards the detergent box (2) and the rotation of the first part (Y) towards the tub (8), around the movement axis (A). [032] In another embodiment of the present invention, in the washer / dryer (1) there is provided a baffle (3) wherein the first part (Y) on one side of the movement axis (A) is heavier than the second part (Z) on the other side. In the mentioned embodiment, out of the first and second parts (Y, Z) which attempt to rotate about the movement axis (A) in different directions because of the forces applied by the cleaning materials coming from the detergent box (2), the part which is subjected to a larger force separates from the stop (9), rotates about the movement axis (A) in the direction determined by the forces applied by the cleaning materials and thus attains a position so as to enable the transfer of the cleaning materials into the tub (8). As the flow of cleaning materials stops, as a consequence of the fact that the forces applied by the cleaning materials are removed and due to the gravitational force acting on the heavier first part (Y), it retains the original position determined by the stop (9) by rotating around the movement axis (A) in the direction determined by the first part (Y). [033] In another embodiment of the present invention, in the washer / dryer (1) there is provided a baffle (3) wherein the first part (Y) at one side of the movement axis (A) having a smaller surface area than the second part (Z) does. In the mentioned embodiment, out of the first and second parts (Y, Z) which attempt to rotate around the movement axis (A) in different directions because of the forces applied by the cleaning materials coming from the detergent box (2), the second part (Z) which is subjected to a larger force because of its larger surface area, separates from the stop (9), rotates around the movement axis (A) in the direction determined by the forces applied by the cleaning materials and thus attains a position so as to enable the transfer of the cleaning materials into the tub (8). As the flow of cleaning materials stops, out of the first and second parts (Y, Z) which attempt to rotate around the movement axis (A) in different directions as a consequence of the fact that the forces applied by the cleaning materials are removed and due to the forces acting on them, applied by the vapor coming from the tub (8), the second part (Z) which is subjected to a larger force because of its larger surface area retains the original position determined by the stop (9) by rotating around the movement axis (A) in the direction determined by the forces applied by the vapor. [034] In one embodiment of the present invention, the baffle (3) has a first and second part (Y, Z), which are positioned at the same plane. In the said embodiment, by means of the stop (9) the baffle (3) is held in a position parallel to the ground. [035] In another embodiment of the present invention, in order to facilitate the motion about the movement axis (A), the baffle (3), having a first and second part (Y, Z) which are positioned at the same plane, is held in an inclined position so that an angle "M" is formed between the baffle (3) and the ground, by means of the stop (9) (Figure 12). [036] In another embodiment of the present invention, the baffle (3) has a first and second part (Y, Z), which are connected to each other at the movement axis (A) and positioned at different planes. The baffle (3) is in a form wherein the movement axis (A) and the first part (Y) are in a position parallel to the ground and the movement axis (A) and the second part (Z) are in an inclined position so as an angle "N" is formed with the ground in order to facilitate the motion around the movement axis (A) (Figure 13). [037] In one embodiment of the present invention, the baffle (3) comprises one or more than one pin (6) positioned on the movement axis (A), used to perform the motion by rotating around the movement axis (A). The pin (6) is placed to a pin housing (17) located where the baffle (3) is located, such as at the detergent box (2). [038] In another embodiment of the present invention, the baffle (3) comprises one or more than one pin housing (7) on the movement axis (A), which enables the motion of the said baffle (3) by rotating around the movement axis (A) it formed and, a cap (10) which prevents the detergent from accumulating on the pin housing (7). At the location where the baffle (3) is placed, for instance at the detergent box (2), there is provided a pin (16) which extends along the interior of the movement axis (A) so as to be covered entirely or partially and which enables the motion of the said baffle (3) by rotating around the movement axis (A) it formed. [039] In another embodiment of the present invention, the washer / dryer (1) comprises a frame (4) where the baffle (3) is attached onto. The frame (4) comprises one or more than one pin housing (27) where the pin (6) moves inside, and a cap (20) which prevents the detergent from accumulating on the pin housing (27). [040] While the stop (9) can be placed on the detergent box (2) or the tub (8) or the frame (4), it can be placed on the pin (6, 16) or the pin housing (J, 17, 27) as well. [041] In the preferred embodiment of the present invention, in the washer / dryer (1) there is provided a baffle (3) having a first and second part (Y, Z) which are connected to each other at the movement axis (A) and positioned at different planes wherein the first part (Y) at one side of the movement axis (A) is heavier and has a smaller surface area than the second part (Z) does. In the mentioned embodiment, as the fluids such as detergent etc start to flow from the detergent box (2), the baffle (3), that is held leaning against the stop (9) as a result of its inclined structure with respect to the ground and due to the weight of the fluids, opens the path that it blocks as a result of the motion of the second part (Z) which is lighter and has a larger surface area than other near the movement axis (A) does wherein the said part moves by rotating around the movement axis (A) towards the tub (8). As the motion of the fluids stops, because of the forces applied by the vapor coming from the tub (8) as a result of the difference in the surface areas of the first (Y) and second parts (Z) and because the first part (Y) of the baffle (3) that is heavier with respect to the movement axis (A) moves the second part (Z) of the baffle (3) that is lighter with respect to other near the movement axis (A) towards the detergent box (2), it is achieved that the baffle (3) retains the original position determined by the stop (9) and thus blocks the path it opens. By the application of the present invention, the path between the detergent box (2) and the tub (8) which is opened only when it is necessary to transfer detergent into the tub (8) is blocked back after the transfer of the detergent and thus the vapor inside the tub (8) is prevented from reaching the detergent box (2). Thereby, it is achieved that detergent is prevented from accumulating inside the detergent box (2) because of the moisture caused by the vapor inside the tub (8), and that the probability that the detergent box (2) gets choked during the following operations as a result of an ac¬ cumulation of detergent is reduced.