Abstract:
A reservoir for holding fluid of a vehicle includes a tank and two brackets integrated with the tank to install the tank in the vehicle in an upper portion of the engine compartment. An attaching portion is arranged with each of the brackets to be fixed to the vehicle. A connecting portion is arranged with each of the brackets to connect the attaching portion to the tank. One of the connecting portions has a notch that is deformed or fractured so that the tank can be moved with respect to the vehicle to absorb an impact force that acts on the tank when the tank receives an impact force larger than a predetermined value. The attaching portion has a plurality of rib portions that is deformable or fracturable so that the tank can be moved with respect to the vehicle to absorb force that acts to the tank when the tank receives a force larger than a predetermined value.

Description:
INCORPORATION BY REFERENCE  
   The present application claims priority under 35 U.S.C. §119 to Japanese Patent Application No. 2003-65923, filed on Mar. 12, 2003. The contents of that application are incorporated herein by reference in their entirety. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates to a reservoir that a bracket is integrated with, more particularly, a reservoir that is installed into engine compartments of vehicles. 
   2. Discussion of the Background 
   Japanese Utility-Model Publication No. 6-16172 discloses a reservoir for various oils such as power steering oil for vehicles. This reservoir comprises a tank made of synthetic resin and a bracket made of metal to attach the tank to a body of the vehicle. A reservoir in which a tank and a bracket are integrally molded of synthetic resin is thus known. 
   Meanwhile, Japanese Laid-Open Patent Application No. 8-258668 discloses a method for protecting a pedestrian who is hit by a vehicle. The pedestrian is thrown up by a front bumper of the vehicle and impacts the engine hood according to the method. Thus, the shock of the pedestrian upon collision with the engine hood is relieved by deformation of the engine hood. That is, the engine hood is deformed downwardly by the collision with the pedestrian, and functions as a shock absorber. Generally, a reservoir is arranged in an upward manner into an engine compartment, because of easy access for oil maintenance, and is rigidly fixed to a body of the vehicle. Therefore, the deformed engine hood collides with the reservoir, and further deformation of the engine hood is prevented by the reservoir. This means that ability of the engine hood to act as a shock absorber for the pedestrian is deteriorated. 
   SUMMARY OF THE INVENTION 
   In view of the foregoing, it is an object of the present invention to provide improved reservoirs. In order to achieve the above and other objects, a first aspect of the present invention provides a reservoir to hold fluid for a vehicle. The reservoir comprises a tank for holding the fluid, a bracket integrated with the tank to install the tank in the vehicle, and an attaching portion arranged with the bracket. The attaching portion is configured so that the tank can be moved for the vehicle to absorb a force that acts to the tank when the tank receives force larger than a predetermined value. 
   A second aspect of the present invention provides another reservoir for a fluid of a vehicle. The reservoir comprises a tank holding the fluid, a bracket integrated with the tank to install the tank in the vehicle, an attaching portion arranged with the bracket to be fixed to the vehicle, and a connecting portion arranged with the bracket to connect the attaching portion to the tank. The connecting portion is configured so that the tank can be moved for the vehicle to absorb a force that acts on the tank when the tank receives a force larger than a predetermined value. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Various other objects, features and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description of the preferred embodiments when considered in connection with the accompanying drawings, in which: 
       FIG. 1  is a side view of a reservoir according to a first embodiment of the present invention; 
       FIG. 2  is a plane view of the reservoir according to the first embodiment; 
       FIG. 3  is an enlarged cross-sectional view of a second attaching portion of the reservoir according to the first embodiment; 
       FIG. 4  is a front view of the reservoir to show forces acting to the reservoir; and 
       FIG. 5  is an enlarged partial view showing a second attaching portion of a reservoir according to a second embodiment of the present embodiment. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   First Embodiment 
   A reservoir according to a first embodiment of the present invention will now be described with reference to  FIGS. 1-4 . The reservoir that is arranged at an upper part in an engine compartment of a vehicle as one of the components of a power steering apparatus which mainly comprises a tank  1  and first and second brackets  2 ,  4 . Oil for the power steering apparatus is stored into the tank  1 . The reservoir is fixed to a body of the vehicle in the engine compartment by the brackets  2 ,  4  and by bolts  9  as fixtures. The material used for the tank  1  and brackets  2 ,  4  is a synthetic resin, and the brackets  2 ,  4  are integrally molded with the tank  1 . 
   The first bracket  2  is horizontally formed on an upper portion of the tank  1 . The first bracket  2  comprises a first attaching portion  29  and a first connecting portion  25  that connects the tank  1  to the first attaching portion  29 . A through hole  219  in which the bolt  9  is inserted is formed in the center of the first attaching portion  29 . Plural arc-shaped concavities (four in this embodiment)  221  are formed on the first attaching portion  29  around the through hole  219  concentrically. As the result, a boss portion  21  around the through hole  29 , a flange portion  23  located at the outside of the arc-shaped concavities  221  and rib portions  24  connecting the flange portion  23  to the boss portion  21  are formed on the attaching portion  29 . The flange portion  23  is continued to the tank  1  along both edges of the first connecting portion  25  and the middle of them. The first connecting portion  25  is separated by the continued flange portions and ribs connecting them so that plural concavities (six in this embodiment) are formed on the first connecting portion  25 . The above-described first bracket  2  functions as a shock absorber for force acting on the reservoir. That is, when the tank  1  receives an excessive force (larger than a predetermined value) of its side direction, plastic deformation furthermore subsidiary fracture occur at the rib portions  24  and plane portions  22  that are thin bottoms of the arc-shaped concavities  221 , which are located between the flange portion  23  and the boss portion  21 . The excessive force that the tank  1  receives is absorbed by the plastic deformation or the subsidiary fracture of the rib portions  24  and the thin plane portions  22 . 
   Meanwhile, as showing by  FIG. 1 , a notch  3  is formed at a middle of the first connecting portion  25 . That is, the section modules of the connecting portion  25  in a side view thereof (the longitudinal direction) are decreased at the portion where the notch  3  is formed. The longitudinal location of a vertex of the notch  3  accords with the location of one of the ribs defining the concavities on the first connecting portion  25 . Therefore, according to the first bracket  2 , the first connecting portion  25  functions as a shock absorber for a force applied in a direction that is parallel to the line O 1 -O 1 . That is, when the tank  1  receives excessive force (larger than a predetermined vale) in an up and down direction, plastic deformation of the subsidiary fracture occurs at notch  3  of the first connecting portion  25 . The excessive force that the tank  1  receives is absorbed by the plastic deformation or the deformation of subsidiary fracture at the notch  3  of the first connecting portion  25 . Further, because the section modules of the connecting portion  25  are small at the notch  3 , stress concentration occurs at the notch  3  rather than a root  27  of the first connecting portion  25 . Therefore, not the root  27  but instead the notch  4  of the first connecting portion is fractured by the excessive force. If the connecting portion  25  is fractured at the root  27 , the tank  1  also may be broken up. Breakage of the tank  1  causes of oil leak. However, according to the above-described first bracket  2 , the connecting portion  25  is not fractured at the root  27 . Therefore, an oil leak is prevented, even if the tank  1  received the excessive force. 
   Similarly, the second bracket  4  is vertically formed on a middle portion in the vertical direction and a side in the horizontal direction of the tank  1 . The second bracket  4  comprises an second attaching portion  49  and a second connecting portion  45  that connects the tank  1  to the attaching portion  49 . A through hole  419  in which the bolt  9  is inserted is formed in the center of the second attaching portion  49 . Plural arc-shaped concavities (four in this embodiment)  421  are formed on the second attaching portion  49  around the through hole  419  concentrically. As the result, a boss portion  41  around the through hole  419 , a flange portion  43  located at the outside of the arc-shaped concavities  421  and rib portions  44  connecting the flange portion  43  to the boss portion  41  are formed on the second attaching portion  49 . The flange portion  43  is continued to the tank  1  along both edges of the connecting portion  45 . The above-described second bracket  4  functions as a shock absorber for force acting on the reservoir. That is, when the tank  1  receives an excessive force (larger than a predetermined vale) in a side direction, plastic deformation of the subsidiary fracture occurs at the rib portions  44  and plane portions  42  that are thin bottom portions of the arc-shaped concavities  421 , which are located between the flange portion  43  and the boss portion  41 . The excessive force that the tank  1  receives is absorbed by the plastic deformation or by the subsidiary fracture of the rib portions  44  and the thin plane portion  42 . 
   With reference to  FIG. 4 , when an engine hood is downwardly deformed by being impacted by a pedestrian who is thrown by a front bumper of a vehicle, the impact strength that makes the engine hood become further deformed acts on the tank  1  as shown by an arrow P. Then, a force as shown by an arrow F acts at the second attaching portion  49 . This directional force causes the plastic deformation or the subsidiary fracture of the rib portions  44  and the thin plane portions  42  because the tank  1  is turned around the line O 2 -O 2  as shown an arrow T 1  by the plastic deformation or the subsidiary fracture of the notch  3 . As the result, the flange portion  43  which is connected with the tank  1  and the boss portion  41  which is fixed by the bolt  9  are able to move relatively in order to absorb the force acting on the reservoir. Furthermore, the P direction force causes the plastic deformation or the subsidiary fracture of the rib portions  24  and the thin plane portions  22  because the tank  1  is inclined in the direction as shown by an arrow T 2 . As the result, the flange portion  23  which is connected with the tank  1  and the boss portion  21  which is fixed by the bolt  9  is able to move relatively in order to absorb force acting on the reservoir. 
   According to the above-described reservoir, since the impact strength acting to the tank  1  is absorbed by the plastic deformation and subsidiary fracture of the first and/or the second brackets  2 , 4 , the injury that the pedestrian who is thrown up the engine hood of the vehicle receives is reduced. Further, since the tank  1  can be turned because of the plastic deformation and subsidiary fracture of the first and/or the second brackets  2 ,  4 , further deformation of the engine hood is not prevented by the tank  1 . Namely, the tank  1  not only has a shock-absorbing function itself and but also does not prevent a shock-absorbing function of the engine hood. Therefore, the pedestrian who is hit by the vehicle and thrown up on the engine hood can be protected. 
   Second Embodiment 
   A reservoir as a second embodiment of the present invention will now be described with reference to  FIG. 5 . Because only the second bracket  4  of the first embodiment is different from the second embodiment, the second bracket  5  of the second embodiment will be described and a description for all other structure will be omitted. The second bracket  5  is vertically formed on middle in the vertical direction and side in the horizontal direction of the tank  1 . The second bracket  5  comprises a second attaching portion  59  and a second connecting portion  55  that connects the tank  1  to the second attaching portion  59 . A through hole  519  in which the bolt  9  is inserted together with a collar  91  is formed in the center of the second attaching portion  59 . Plural arc-shaped concavities (two in this embodiment)  521  are formed on the second attaching portion  59  around the through hole  519  concentrically. As the result, a boss portion  51  around the through hole  519 , a flange portion  53  located at the out side of the arc-shaped concavities  521  and rib portions  54  connecting the flange portion  53  to the boss portion  51  are formed on the second attaching portion  59 . The flange portion  53  is continued to the tank  1  along both edges of the second connecting portion  45 . A slit  6  that is continued to the through hole  59  is upwardly formed at the second attaching portion  59 . The width of the slit  6  is defined to be slightly narrower than the diameter of the collar  91 . The above-described second bracket  5  functions as a shock absorber for impact strength from an impact in the direction shown by the arrow P. That is, when the tank  1  receives excessive force (larger than a predetermined value) in the ups and down direction, thereof, the bolt  9  and the collar  91  are detached from the through hole  519 . Then, the second attaching portion  59  is deformed so as to be widened such that the collar  91  goes through the same and the collar  91  slides on the slit  6 . Therefore, the impact strength that the tank  1  receives is absorbed by the deformation of the attaching portion  59  and the friction between the collar  91  and walls defining the slit  6 . Further, because the bolt  9  is detached from the through hole  519 , the tank  1  is being able to be turned. Therefore, further deformation of the engine hood is not prevented by the tank  1 . 
   Although both of the first and the second brackets  2 ,  4  that function as the shock absorber are used according to the first and the second embodiments, it is possible that only one of the first and second brackets  2 ,  4  is used. Further, it is possible that one of the first and the second brackets  2 ,  4  that functions as the shock absorber and another bracket that does not function as such shock absorber are used. Furthermore, although both of the attaching portion  29  and the connecting portion  25  of the first bracket  2  function as the shock absorber, it is possible that a bracket that functions as the shock absorber at only one of the attaching portion and connecting portion is used. 
   Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is thereby to be understood that within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described herein.