Patent Application
20100224454
The present invention relates to a shock absorber and, more particularly, to a stepless pressure-varying shock absorber.
A shock absorber generally includes a member that can be compressed or stretched when subjected to shock or impact so as to absorb the shock or impact. Shock absorbers have various applications in daily lives and can be of simple designs such as springs utilized in beds and chairs or of complicated designs in various vehicles, mechanical equipment, and houses for shock absorbing purposes.
Thus, a need exists for a shock absorber with desired damping effect.
A shock absorber according to the preferred teachings of the present invention includes a cylinder having a chamber. A partitioning board is fixed in the chamber and separates the chamber into first and second compartments spaced in a longitudinal axis of the cylinder. The first and second compartments receive a damping fluid. The partitioning board includes a first through-hole extending along the longitudinal axis. The first and second compartments are in communication with each other via the first through-hole. A buffering disc is mounted in the chamber and forms a bottom end of the second compartment. A rod is slidably received in the chamber and slideably extends through the first through-hole of the positioning board. A damping valve is securely mounted around the rod to move therewith. The damping valve is slideably received in the first compartment. The partitioning board is intermediate the damping valve and the buffering disc along the longitudinal axis. The rod has downwardly decreasing cross sections. A gap is formed between an inner periphery of the first through-hole of the partitioning board and an outer periphery of the rod. The buffering disc moves along the longitudinal axis when the rod moves in the chamber along the longitudinal axis.
When the rod moves downward, an area of the gap decreases gradually to gradually increase resistance to the damping fluid flowing from the first compartment into the second compartment via the first through-hole.
In the most preferred form, the partitioning board further includes a second through-hole in communication with the first and second compartments. The second through-hole is spaced from the first through-hole in a radial direction perpendicular to the longitudinal axis. The second through-hole includes an upper portion having a socket. A mesh is mounted in the first compartment. A space defined between the mesh and a side of the partitioning board facing the first compartment. A ball is movably received in the space and has a diameter larger than the second through-hole. The mesh limits floating of the ball in the space. The damping fluid is flowable from the second compartment through the second through-hole and the mesh into the first compartment when the ball is received in the space and is disengaged from the socket. The ball blocks the second through-hole when the ball is received in the socket.
The present invention will become clearer in light of the following detailed description of illustrative embodiments of this invention described in connection with the drawings.
A stepless pressure-varying shock absorber according to the preferred teachings of the present invention is shown in the drawings and can be utilized in various vehicles, mechanical equipment, houses, etc for shock absorbing purposes.
According to the preferred form shown, the stepless pressure-varying shock absorber includes a cylinder 1 having a chamber. A partitioning board 11 is fixed in the chamber and separates the chamber into first and second compartments 12 and 13 spaced along a longitudinal axis of the cylinder 1. The first and second compartments 12 and 13 receive damping fluid such as oil, gas, liquid, etc. The partitioning board 11 includes a first through-hole 15 extending along the longitudinal axis and having an inner periphery. The first and second compartments 12 and 13 are in communication with each other via the first through-hole 15. A buffering disc 10 is mounted in the chamber and below the partitioning plate 11. The buffering disc 10 forms a bottom end of the second compartment 13.
According to the preferred form shown, a rod 14 is slidably received in the chamber and slideably extends through the first through-hole 15 of the positioning board 11. A gap is formed between the inner periphery of the first through-hole 15 of the partitioning board 11 and an outer periphery of the rod 14. An upper end of the rod 14 extends out of the cylinder 1 and is attached to an object including but not limited to a vehicle, a house, mechanical equipment, etc for absorbing shock and vibration imparted to the object.
A damping valve 141 is securely mounted around the rod 14 to move therewith. The damping valve 141 is slideably received in the first compartment 12. The partitioning board 11 is intermediate the damping valve 141 and the buffering disc 10 along the longitudinal axis. The buffering disc 10 moves up and down along the longitudinal axis when the rod 14 moves up and down in the chamber along the longitudinal axis due to impact or vibration imparted to the rod 14 from the object. Specifically, when the rod 14 moves downwardly, the damping fluid flows from the first compartment 12 into the second compartment 13, and the buffering disc 10 moves downward. On the other hand, when the rod 14 moves upwardly, the damping fluid flows from the second compartment 13 into the first compartment 13, and the buffering disc 10 moves upward. Vibration imparted to the rod 14 is absorbed while the damping fluid flows from the first compartment 12 to the second compartment 13 or from the second compartment 13 to the first compartment 12, providing a buffering effect.
According to the preferred form shown, the rod 14 has downwardly decreasing cross sections. In the most preferred form shown, the rod 14 has circular cross sections, and the circular cross sections of the rod 14 gradually decrease toward the buffering disc 10. Thus, when the rod 14 moves downward, an area of the gap gradually changes to gradually increase resistance to the damping fluid flowing from the first compartment 12 into the second compartment 13 via the first through-hole 15. Specifically, the area of the gap allowing the damping fluid to flow from the first compartment 12 into second compartment 13 gradually decreases when the rod 14 moves downward. The damping effect is, thus, increased gradually during the downward movement of the rod 14. Thus, the shock absorber according to the preferred teachings of the present invention can provide differing damping effects and differing shock absorbing effects responsive to differing vibration extents, and the pressure of the flowing damping fluid varies in a stepless manner. It can be appreciated that the rod 14 can have other cross sections other than circular. As an example, the rod 14 can have polygonal cross sections.
In the most preferred form shown, the partitioning board 11 further includes a second through-hole 111 in communication with the first and second compartments 12 and 13. The second through-hole 111 is spaced from the first through-hole 15 in a radial direction perpendicular to the longitudinal axis. The second through-hole 111 includes an upper portion having a socket 112 with a diameter larger than that of a lower portion of the second through-hole 111. A mesh 114 is mounted in the first compartment 12. A space 116 is defined between the mesh 114 and a side of the partitioning board 11 facing the first compartment 12. A ball 113 is movably received in the space 116 and has a diameter larger than the second through-hole 111. The mesh 114 limits floating of the ball 113 in the space 116. When the rod 14 moves upward, the damping fluid is flowable from the second compartment 13 through the second through-hole 111 and pushes the ball 113 upward into in the space 116. Thus, the ball 113 is disengaged from the socket 112 so that the damping fluid is continuously flowable from the second compartment 13 into the first compartment 12 via the first through-hole 15 and via the second through-hole 111 and the mesh 114. When the rod 14 moves downward, the ball 113 is pushed into the socket 112 by the damping fluid flowing from the first compartment 12 through the mesh 114 into the space 116. Thus, the ball 113 blocks the second through-hole 111 when the rod 14 moves downward, and the damping fluid flows from the first compartment 12 to the second compartment 13 via the first through-hole 13.
In the most preferred form shown, an elastomer 142 is mounted between the damping valve 141 and an upper end of the cylinder 1 to reduce impact between the damping valve 141 and the upper end of the cylinder 1 and to provide a sealing effect preventing leakage of the damping fluid. Furthermore, a first attachment member 17 is provided on an outer periphery of the cylinder 1, a second attachment member 18 is provided on the upper end of the rod 14 outside of cylinder 1, and an elastic element 19 is mounted between the first and second attachment members 17 and 18 to provide enhanced damping effect.
Thus since the invention disclosed herein may be embodied in other specific forms without departing from the spirit or general characteristics thereof, some of which forms have been indicated, the embodiments described herein are to be considered in all respects illustrative and not restrictive. The scope of the invention is to be indicated by the appended claims, rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.
