Abstract:
A vehicle shock absorber system configured with more than one pressure cylinder that provides advantageous damping characteristics for different loads. There is provided a vehicle shock absorber system having a primary pressure cylinder including upper and lower primary chambers separated by a primary piston head, an auxiliary pressure cylinder including upper and lower auxiliary chambers separated by an auxiliary piston head, a first connection conduit connecting the upper primary chamber and the upper auxiliary chamber, a second connection conduit connecting the lower primary chamber and the lower auxiliary chamber, and a cylinder valve arrangement configured to regulate fluid flow to the auxiliary pressure cylinder.

Description:
FIELD OF THE INVENTION 
       [0001]    The subject matter of the present application relates to a shock absorber system and components thereof, and, more particularly, to a system configured with more than one damping resistance value. 
       BACKGROUND OF THE INVENTION 
       [0002]    Vehicle shock absorber systems are configured to provide a damping effect within a predetermined value range. The range is selected in accordance with an expected load on the system, such as, a heavy load or a light load. 
         [0003]    For example, a system can be configured for a vehicle, or portion of a vehicle, which typically carries a relatively heavy load to provide suitable shock absorption within a predetermined value range suitable for carrying heavy loads. However, that system may provide poor performance, at least comfort-wise to a passenger of the vehicle, when the vehicle, or portion thereof, is free of heavy loads, especially when travelling on a high quality or smooth road. 
         [0004]    Conversely, a system can be configured for a vehicle, or portion of a vehicle, which typically carries a relatively light load to provide suitable shock absorption within a predetermined value range suitable for normal usage of carrying light loads. However, that system may provide poor performance, at least comfort-wise to the passenger of the vehicle, when the vehicle, or portion thereof, is carrying an unusual, relatively heavy load or is travelling on a low-quality or bumpy road, or off-road. 
         [0005]    Furthermore, the spring and shock of typical vehicle shock absorber systems have to be in tune with each other. Therefore, simply changing the spring rate, without tuning the shock accordingly, does not provide an adequate solution to the problem described above. 
       SUMMARY OF THE INVENTION 
       [0006]    It has been found that a vehicle shock absorber system configured with more than one pressure cylinder can provide advantageous damping characteristics for different loads. 
         [0007]    In accordance with a first aspect of the subject matter of the present application, there is provided a vehicle shock absorber system having a primary pressure cylinder including upper and lower primary chambers separated by a primary piston head, an auxiliary pressure cylinder including upper and lower auxiliary chambers separated by an auxiliary piston head, a first connection conduit connecting the upper primary chamber and the upper auxiliary chamber, a second connection conduit connecting the lower primary chamber and the lower auxiliary chamber, and a cylinder valve arrangement configured to regulate fluid flow to the auxiliary pressure cylinder. 
         [0008]    In accordance with a further aspect of the subject matter of the present application, there is provided a vehicle shock absorber system accessory having an auxiliary pressure cylinder. The auxiliary pressure cylinder includes an auxiliary piston head configured to remain in a single position within the auxiliary pressure cylinder and to separate the auxiliary pressure cylinder into upper and lower auxiliary chambers, an upper auxiliary chamber inlet in fluid communication with the upper auxiliary chamber, and a lower auxiliary chamber inlet in fluid communication with the lower auxiliary chamber. 
         [0009]    It will be understood that the upper and lower auxiliary chamber inlets are configured for connection to, i.e., for use with, a primary pressure cylinder of a vehicle shock absorber system. 
         [0010]    It will also be understood that the above-said is a summary, and that any of the aspects or embodiments mentioned above may further include any of the features described in connection with any of the other aspects or embodiments described herein below. Specifically, the following features, either alone or in combination, may be applicable to any of the above aspects or embodiments:
       A. A vehicle shock absorber system or accessory that includes a first connection conduit connected to an upper auxiliary chamber and a second connection conduit connected to a lower auxiliary chamber. More precisely, the first connection conduit can be connected to an upper auxiliary chamber inlet and the second connection conduit can be connected to a lower auxiliary chamber inlet.   B. An auxiliary piston head that is configured to remain in a single position within an auxiliary pressure cylinder, and to separate the auxiliary pressure cylinder into upper and lower auxiliary chambers. Stated differently, the upper and lower auxiliary chambers can have predetermined volumes.   C. A vehicle shock absorber system or accessory that includes a cylinder valve arrangement. The cylinder valve arrangement can include a first valve located in a first connection conduit and/or a second valve located in a second connection conduit.   D. A vehicle shock absorber system that includes a bypass conduit connecting upper and lower primary chambers.   E. A vehicle shock absorber system that includes a bypass valve arrangement configured to regulate fluid flow through a bypass conduit.   F. A bypass valve arrangement that includes at least one valve located in a bypass conduit. The at least one valve can be a first bypass valve. The bypass valve arrangement can further include a needle valve.   G. One or more, or all, of the valves of the system can be configured to be manually operated.   H. One or more, or all, of the valves of the system can be configured to be automatically operated.   I. One or more, or all, of the valves of the system can be configured to bring the system to three operative states, namely—a first operative state where only the primary pressure cylinder is operative, a second operative state where only the primary pressure cylinder and the auxiliary pressure cylinder are operative, and a third operative state where only the primary pressure cylinder and bypass conduit are operative.   J. A primary pressure cylinder that is configured with a predetermined primary damping resistance value (R 1 ).   K. An auxiliary pressure cylinder that is configured with a predetermined auxiliary damping resistance value (R 2 ).   L. A bypass conduit that is configured with a predetermined bypass resistance value (R 3 ).       
 
         [0023]    More precisely, a bypass valve arrangement of the bypass conduit can be configured with the predetermined bypass resistance value (R 3 ). The predetermined bypass resistance value (R 3 ) can have no resistance (i.e.: R 3 =0) when the bypass conduit is in an open state (e.g., when all valves thereof are open). In an embodiment where the bypass conduit further includes, for example, a needle valve, the predetermined bypass resistance value (R 3 ) can be configured to a zero value or another value. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0024]    For a better understanding of the subject matter of the present application, and to show how the same may be carried out in practice, reference will now be made to the accompanying drawing, in which: 
           [0025]      FIG. 1  is a schematic view of a vehicle shock absorber system including a vehicle shock absorber system accessory. 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    Referring to  FIG. 1 , there is illustrated a vehicle shock absorber system  10 . 
         [0027]    The system  10  includes a primary pressure cylinder  12 A and a vehicle shock absorber system accessory  14 . 
         [0028]    Primary pressure cylinder  12 A includes an upper primary chamber  16 A, a lower primary chamber  18 A, and a primary piston head  20 A separating upper primary chamber  16 A and lower primary chamber  18 A. Piston head  20 A can include a piston head valve (not shown). The piston head valve can have a fixed cross section or a pressure sensitive cross section that provides pressure or speed dependant damping, sensitive to the speed of the load, e.g., opens more under heavy pressure. The piston head valve can include shims that bend under a load. 
         [0029]    Primary piston head  20 A can be configured for movement within primary pressure cylinder  12 A, which in turn causes movement of a fluid therein (not shown). The movement of primary piston head  20 A within the fluid of primary pressure cylinder  12 A can provide a damping effect on the shock absorption of a vehicle (not shown) to which system  10  is connected. More precisely, primary pressure cylinder  12 A can be configured with a predetermined primary damping resistance value R 1 . 
         [0030]    More specifically, primary piston head  20 A can be connected to a primary piston rod  22 A, which in turn is connected to the vehicle. For example, an eyelet  23 A of primary piston rod  22 A can be connected to the vehicle&#39;s wheel axle support (not shown). Similarly, a primary cylinder connector  24 A, located at an opposing side of primary pressure cylinder  20 A from primary piston rod  22 A, i.e., adjacent to upper primary chamber  16 A in this non-limiting example, can be connected to a different portion of the vehicle, such as, its chassis. 
         [0031]    During operation of the vehicle, primary piston rod  22 A can move vertically in two opposite directions: a first “backward” direction D B  (away from the ground), and a second “forward” direction D F  (towards the ground) (“backward” and “forward” being relative to the direction of primary piston rod  22 A towards the ground), in a manner known to pressure cylinders. 
         [0032]    Primary pressure cylinder  12 A includes a first upper primary chamber inlet  25 A 1  in fluid communication with upper primary chamber  16 A, and a first lower primary chamber inlet  25 A 2  in fluid communication with lower primary chamber  18 A. First upper primary chamber inlet  25 A 1  and first lower primary chamber inlet  25 A 2  are used to connect primary pressure cylinder  12 A to accessory  14 , or, more precisely, to a first connection conduit  24  and a second connection conduit  26  thereof. 
         [0033]    Primary pressure cylinder  12 A can further include a second upper primary chamber inlet  25 A 3  in fluid communication with upper primary chamber  16 A, and a second lower primary chamber inlet  25 A 4  in fluid communication with lower primary chamber  18 A. Second upper primary chamber inlet  25 A 3  and second lower primary chamber inlet  25 A 4  are used to connect primary pressure cylinder  12 A to a bypass conduit  30 . 
         [0034]    System  10  further includes an auxiliary pressure cylinder  12 B. Auxiliary pressure cylinder  12 B includes an upper auxiliary chamber  16 B, a lower auxiliary chamber  18 B, and an auxiliary piston head  20 B separating upper auxiliary chamber  16 B and lower auxiliary chamber  18 B. Auxiliary piston head  20 B can include a piston head valve (not shown), as described above. 
         [0035]    Auxiliary pressure cylinder  12 B can be configured with a predetermined auxiliary damping resistance value R 2 . 
         [0036]    In contrast with primary pressure cylinder  12 A, auxiliary piston head  20 B can be configured to remain in a single, stationary position within auxiliary pressure cylinder  12 B. In such a case it will be understood that upper and lower auxiliary chambers  16 B,  18 B each have a fixed volume. 
         [0037]    Auxiliary pressure cylinder  12 B includes an upper auxiliary chamber inlet  25 B 1  in fluid communication with upper auxiliary chamber  16 B, and a lower auxiliary chamber inlet  25 B 2  in fluid communication with lower auxiliary chamber  18 B. Upper auxiliary chamber inlet  25 B 1  and lower auxiliary chamber inlet  25 B 2  are used to connect auxiliary pressure cylinder  12 B to primary pressure cylinder  12 A. 
         [0038]    First connection conduit  24  can connect upper primary chamber  16 A and upper auxiliary chamber  16 B. More precisely, first connection conduit  24  can connect first upper primary chamber inlet  25 A 1  and upper auxiliary chamber inlet  25 B 1 . To elaborate, first connection conduit  24  can be in fluid communication with both upper primary chamber  16 A and upper auxiliary chamber  16 B. 
         [0039]    Second connection conduit  26  can connect lower primary chamber  18 A and lower auxiliary chamber  18 B. More precisely, second connection conduit  26  can connect first lower primary chamber inlet  25 A 2  and lower auxiliary chamber inlet  25 B 2 . To elaborate, second connection conduit  26  can be in fluid communication with both lower primary chamber  18 A and lower auxiliary chamber  18 B. 
         [0040]    Accessory  14  can include a cylinder valve arrangement  28  configured to regulate fluid flow to auxiliary pressure cylinder  12 B. Cylinder valve arrangement  28  includes a first valve  28 A located in first connection conduit  24  and a second valve  28 B located in second connection conduit  26 . 
         [0041]    First and second valves  28 A,  28 B can be configured to be brought to open or closed operative states, which respectively permit or prevent fluid passage through first and second connection conduits  24 ,  26 . 
         [0042]    As mentioned above, system  10  includes a bypass conduit  30 . Bypass conduit  30  connects upper primary chamber  16 A and lower primary chamber  18 A. More precisely, bypass conduit  30  connects second upper primary chamber inlet  25 A 3  and second lower primary chamber inlet  25 A 4 . Bypass conduit  30  is in fluid communication with upper primary chamber  16 A and lower primary chamber  18 A. 
         [0043]    Bypass conduit  30  can further include a bypass valve arrangement  32  configured to regulate fluid flow through bypass conduit  30 . 
         [0044]    Bypass valve arrangement  32  includes a first bypass valve  32 A configured to permit or prevent fluid passage through bypass conduit  30 . 
         [0045]    Bypass valve arrangement  32  can be configured with a damping resistance value R 3 . For example, when bypass valve  32 A is open, the damping resistance value R 3  can be zero. 
         [0046]    Optionally, bypass valve arrangement  32  can further include an additional valve, such as, a needle valve  32 B configured to provide a desired resistance. 
         [0047]    The vehicle shock absorber system  10  can have three different operative modes. 
         [0048]    In a first operative mode, in which cylinder valve arrangement  28  is in a closed state, i.e., first valve  28 A and second valve  28 B are closed, and bypass valve arrangement  32  is in a closed state, i.e., first bypass valve  32 A is closed, the damping effect provided by system  10  on the vehicle is equal to the primary damping resistance value R 1  of primary pressure cylinder  12 A. 
         [0049]    In a second operative mode of system  10 , in which cylinder valve arrangement  28  is in an open state, i.e., first valve  28 A and second valve  28 B are open, and bypass valve arrangement  32  is in a closed state, the damping effect provided by system  10  on the vehicle is equal to an inverse of the sum of the inverse resistance values (for system resistance R, 1/R=1/R 1 +1/R 2 ). In a non-limiting example, if both the primary and auxiliary damping resistance values (R 1 , R 2 ) are of equal magnitude, the resistance of system  10  is halved. 
         [0050]    It will be appreciated that the first operative mode may be preferred, for example, for a vehicle carrying a relatively heavy load, and that the second operative mode may be preferred for that vehicle when it is carrying a relatively lighter load. 
         [0051]    Cylinder valve arrangement  28  can be configured to be switched manually between the first and second operative modes, and/or can be configured to be switched automatically between those two modes. For example, a vehicle computer system (not shown) may be configured to detect the load carried by the vehicle or on vehicle shock absorber system  10 , and may automatically switch cylinder valve arrangement  28  to a desired mode. The automatic switching can also be operated dynamically, i.e., according to a change in road conditions when the vehicle is in motion. Additionally or alternatively, system  10  can further include a manual switch (not shown) which is configured to change the operative mode. The switch can be located in a driver&#39;s compartment (not shown) of the vehicle. It will be understood that in addition to the manual and automatic options mentioned above, cylinder valve arrangement  28  may also be configured to allow direct manual adjustment of valves  28 A,  28 B themselves at their respective locations. 
         [0052]    In a third operative mode of system  10 , when bypass valve arrangement  32  is in an open state, i.e., first bypass valve  32 A is open (and assuming bypass conduit  30  is devoid of optional needle valve  32 B), the damping effect provided by system  10  is effectively zero as the fluid can merely pass through bypass conduit  30  without resistance. Bypass valve arrangement  32  can be switched to, and from, its open state from, and to, either the first or second operative mode. 
         [0053]    Also, it will be understood that bypass valve arrangement  32  can be brought to open or closed operative modes in any of the manners described above in connection with the cylinder valve arrangement  28  (manual, automatic, remote, proximate, etc.). Similarly, needle valve  32 B may be similarly adjustable in such manner 
         [0054]    The device of the present invention can be used in tandem with the primary shock (not shown) of a vehicle. The different levels of dampening, e.g., zero, 1/2R and 1R is added to the dampening value of the primary shock Z, for a total dampening value (according to this example) of: Z, Z+1/2R, or Z+R, depending on the mode of operation. In a non-limiting example, Z is configured to support a vehicle weight of 2.5 tons and R is configured to support an added weight of 2 tons. Support for an unloaded, empty vehicle of 2.5 tons would be provided by the mode where the bypass is open and only the primary shock is working (R=0, a total dampening value of Z). Support for the same vehicle with an added load of 1 ton (half the added weight that R is configured for), i.e., a total weight of 3.5 tons (the vehicle plus the added weight), would be provided by the mode where the bypass is closed and the connection to the secondary valve is open (a total dampening value of Z+1/2R). Support for the vehicle with a full load of 2 tons, i.e., a total weight of 4.5 tons, would be provided by the mode where the bypass is closed and the connection to the secondary valve is closed (a total dampening value of Z+R). In this way, the device of the present invention makes it possible to tune the shock in accordance with a change in spring rate of the vehicle on the fly and still have good working suspension. 
         [0055]    The description above includes an exemplary embodiment and details, and does not exclude non-exemplified embodiments and details from the claim scope of the present application. While certain embodiments of the disclosed subject matter have been described, so as to enable one of skill in the art to practice the present invention, the preceding description is intended to be exemplary only. It should not be used to limit the scope of the disclosed subject matter, which should be determined by reference to the following claims.