JP3995645B2 - Hydraulic shock absorber - Google Patents

Description

  The present invention relates to a vibration exciter used for measuring damping force characteristics and the like of a hydraulic shock absorber used in a suspension device such as a vehicle.

  As an apparatus for measuring the damping force characteristics of a hydraulic shock absorber used in a suspension device of a vehicle such as an automobile, the one shown in Non-Patent Document 1 can be exemplified.

  That is, as shown in FIG. 3, the vibration exciter 52 having the lower attachment portion 57 to which the lower end portion of the hydraulic shock absorber 51 is attached and the tip end portion of the piston rod 53 protruding from the hydraulic shock absorber 51 are fixedly positioned. A load detector 63 having an upper mounting portion 58 to be fixed and a displacement meter 54 provided on the vibration exciter 52 are provided, and a displacement signal from the displacement meter 54 and a load signal from the load detector 63 are received by an amplifier 55. By amplifying, the damping force characteristic with respect to the piston speed of the hydraulic shock absorber 51 is output to the display means 56.

And as a vibration apparatus used for this measuring apparatus, a vibration exciter 52, a lower attachment part 57 provided in the vibration exciter 52, an upper attachment part 58 provided in the load detector 63, Can be illustrated.
“Automotive Standard Suspension Cylindrical Shock Absorber” by the Society of Automotive Engineers, Japan Society of Automotive Engineers, revised on March 30, 1992, P11-P12

  The vibration device used in the measuring device of Non-Patent Document 1 is not particularly problematic, but the following problems can be considered.

  That is, when attaching the hydraulic shock absorber 51 having the attachment eye 59 at the lower end to the lower attachment portion 57, 1) inserting the attachment pin 60 extending laterally from the lower attachment portion 57 into the attachment eye 59; 2) Since the inserted mounting pin 60 is tightened with the nut 62 through the washer 61 and the like so that the mounting eye 60 does not loosen with respect to the lower mounting portion 57, these mounting operations are troublesome. It is.

  Further, when the hydraulic shock absorber 51 that does not include the attachment eye 59 is attached to the lower attachment portion 57, it cannot be attached with the above-described structure. Therefore, it is necessary to intervene another member, and the attachment work is further complicated. .

  Accordingly, an object of the present invention is to provide a vibration exciter for a hydraulic shock absorber having a mechanism that can be easily attached regardless of the shape of the lower end portion of the hydraulic shock absorber.

In order to achieve the above object, the means of the present invention includes a vibration exciter, a lower table attached to the vibration exciter, a lower attachment portion fixed to the center of the lower table, and a lower side. A hemispherical mounting surface formed on the upper surface of the mounting portion, a pair of hydraulic cylinders standing from both ends of the lower table, an upper table coupled to the piston rod of each hydraulic cylinder and having a hole in the center; It consists of a gate-type machine frame that is fixed to both ends of the vibrator, and an upper mounting part that is fixed to the upper part of the machine frame so as to face the lower mounting part. The mounting eye is placed on the mounting surface, and the piston rod of the hydraulic shock absorber is fixed to the upper mounting portion through the hole, and the hydraulic cylinder is contracted to form the edge of the hole of the upper table. The rod end cylinder end of the hydraulic shock absorber is locked with It is characterized in that to.

In this case, it is preferable that a universal joint is provided in the upper mounting portion, and the piston rod tip is fixed through the universal joint.

According to the present invention, when the piston rod of the hydraulic cylinder is contracted, the upper table is lowered, and the hydraulic shock absorber in which the end of the rod side cylinder is locked at the edge of the hole faces the lower table side. And descend.
At this time, since the mounting surface is hemispherical, when the hydraulic shock absorber is lowered, the mounting eye follows the arc surface of the mounting surface as it is lowered, and is automatically aligned and placed at a predetermined position. Is done.
When the hydraulic cylinder is locked in this state, the hydraulic shock absorber is accurately attached at a predetermined position.
Therefore, when the vibration exciter is operated in this state, the lower table moves up and down, and with the hydraulic shock absorber fixed, the piston rod extends and retracts freely and repeats up and down movement. The damping force characteristic for can be measured.

  Hereinafter, an embodiment in which the present invention is embodied in a damping force measuring apparatus for a hydraulic shock absorber for an automobile will be described with reference to the drawings.

As shown in FIGS. 1 and 2, the measuring device 1 includes a vibrator 2 constituting a base, a lower table 3 attached to the vibrator 2 so as to be vibrated, and a center of the lower table 3. A lower mounting portion 4 fixed to the upper surface, a hemispherical mounting surface 11 formed on the upper surface of the lower mounting portion 4, a pair of hydraulic cylinders 13 rising from both ends of the lower table 3, An upper table 14 that is coupled to the piston rod 13a and has a hole 16 in the center, a portal machine frame 18 that is fixed to both ends of the vibrator 2 and stands upright, and the lower attachment above the machine frame 18 The upper mounting portion 8 is fixed so as to face the portion 4.
Then, the cylinder-side mounting eye 12 of the hydraulic shock absorber 6 to be measured is placed on the mounting surface 11 and the piston rod 7 of the hydraulic shock absorber is fixed to the upper mounting portion 8 through the hole. The hydraulic cylinder 13 is contracted and the rod side cylinder end of the hydraulic shock absorber is locked by the hole 16 edge 15 of the upper table 14 .
Details will be described below.

  The lower mounting portion 4 is formed in a cubic shape as a whole, and has a hemispherical mounting surface 11 at the center of the upper surface, and a mounting eye 12 at the lower end of the hydraulic shock absorber 6 is displayed on the mounting surface 11. It is arranged at a predetermined position following the arc surface of the mounting surface 11 simply by placing the mounting surface 11.

  The fixing member 5 includes two hydraulic cylinders 13 whose base ends are fixed to both ends of the lower table 3, and an upper table 14 fixed to a distal end portion of a piston rod 13 a protruding and retracting from the cylinder 13. The upper table 14 is provided with a hole 16 through which the piston rod 7 of the hydraulic shock absorber 6 can be inserted and the edge 15 of which the rod side end of the hydraulic shock absorber 6 is locked.

  Accordingly, the lower end portion of the hydraulic shock absorber 6 with the piston rod 7 inserted into the hole 16 is disposed on the lower mounting portion 4, and the piston rod 13a of the hydraulic cylinder 13 is moved by the operation of a hydraulic source (not shown). When the upper table 14 is lowered by contraction, the hydraulic shock absorber 6 is pushed toward the lower table side 3 in a state in which the rod side end is locked at the edge 15 of the hole 16. .

  The upper mounting portion 8 is fixed to the lower surface of the central portion of a portal-shaped machine casing 18 extending upward from both ends of the vibrator 2, a universal joint 19 to which the tip end portion of the piston rod 7 is fixed, and a load And a load cell 20 as a detector.

  The exciter 2 is provided with a displacement meter 23. The amplifier 21 amplifies the load signal from the load cell 20 and the displacement signal from the displacement meter 23, whereby the piston of the hydraulic shock absorber 6 is displayed on the display means 22. A damping force characteristic with respect to speed is output.

  In order to measure the damping force characteristic of the hydraulic shock absorber 6 having the mounting eye 12 at the lower end using the measuring device 1 configured as described above, as shown in FIG. After the piston rod 7 of the hydraulic shock absorber 6 to be measured is inserted into the hole 16 of the upper table 14, the lower end portion of the hydraulic shock absorber 6 is placed on the mounting surface 11 of the lower mounting portion 4.

  In this state, the piston rod 7 is extended, and its upper end is fixed to the universal joint 19 of the upper mounting portion 8.

  Next, when the piston rod 13a of the hydraulic cylinder 13 is contracted by operating a hydraulic source (not shown), the upper table 14 is lowered and the hydraulic pressure in which the end of the rod side cylinder is locked by the edge 15 of the hole 16 thereof. The shock absorber 6 descends toward the lower table 3 side.

  At this time, since the mounting surface 11 is hemispherical, when the hydraulic shock absorber 6 is lowered, the mounting eye 12 follows the arc surface of the mounting surface 11 as the hydraulic shock absorber 6 is lowered, as shown in FIG. It is automatically aligned and placed at a predetermined position.

  When the hydraulic cylinder 13 is locked in this state, the hydraulic shock absorber 6 is accurately attached to a predetermined position of the measuring device 1.

  Therefore, when the vibration exciter 2 is operated in this state, the lower table 3 moves up and down, and the piston rod 7 extends and retracts freely with the hydraulic shock absorber 6 fixed, and repeats the vertical movement. As a result of the operation, a load signal is output from the load cell 20 and a displacement signal is output from the displacement meter 23. By amplifying these values, a damping force characteristic with respect to the piston speed of the hydraulic shock absorber 6 is displayed on the display means 22.

  As described above, according to this embodiment, when the hydraulic shock absorber 6 is attached to the measuring device 1, after the piston rod 7 of the hydraulic shock absorber 6 to be measured is inserted into the hole 16 of the upper table 14, this hydraulic shock absorber is inserted. Since the lower end of 6 is placed on the mounting surface 11 of the lower mounting section 4 and the upper table 14 is lowered, the hydraulic shock absorber 6 can be mounted at a predetermined position, so that the operation is simple and the time can be shortened. .

  In particular, since the mounting surface 11 of the lower mounting portion 4 is hemispherical, the automatic centering function for the lower mounting portion 4 can be exhibited regardless of the size of the mounting eye 12 of the hydraulic shock absorber 6, and the accurate damping force Characteristics can be measured.

  Further, since the hemispherical mounting surface 11 is used, even if the hydraulic shock absorber 6 without the mounting eye 12 has a diameter that can be arranged in the mounting surface 11, the automatic core function can be exhibited, and the device itself can be used for general purposes. It can be sexual.

  In addition, the universal joint 19 is used for the upper mounting portion, and the tip of the piston rod 7 is fixed via the joint 19, so that the centering function can be exhibited on the upper mounting portion 8 side, and more accurate damping force characteristics are measured. Can do.

  In addition, this invention is not limited to the said embodiment, For example, it can also be changed and embodied as follows.

  1) In the present embodiment, the upper table 14 is raised and lowered by the hydraulic cylinder 13, but an air pressure other than hydraulic pressure, an electric motor, or the like may be used.

  2) In order to fix the hydraulic shock absorber 6, the upper table 14 having the hole 16 to which the rod side end is locked is used. However, the present invention is not limited to this. A mechanism that grasps and descends downward may be employed.

  3) In the present embodiment, the damping force characteristics of the hydraulic shock absorber 6 provided with the mounting eye 12 are measured. However, a hydraulic shock absorber without the mounting eye 12 or a strut type hydraulic shock absorber may be measured.

It is a partially broken front view showing a damping force measuring device of a hydraulic shock absorber showing the best mode for carrying out the present invention. In FIG. 1, it is a partially broken front view which shows the state which raised the upper table. It is a front view which shows a conventional structure.

Explanation of symbols

2 Exciters (exciting means)
DESCRIPTION OF SYMBOLS 3 Lower table 4 Lower attachment part 5 Fixed member 6 Hydraulic shock absorber 7 Piston rod 8 Upper attachment part 11 Mounting surface 13 Hydraulic cylinder 13a Piston rod 14 Upper table 15 Edge part 16 Hole part 19 Universal joint

Claims (2)

A vibrator, a lower table attached to the vibrator so as to be able to vibrate, a lower attachment part fixed to the center of the lower table, a hemispherical attachment surface formed on the upper surface of the lower attachment part, A pair of hydraulic cylinders that stand from both ends of the lower table, an upper table that is coupled to the piston rod of each hydraulic cylinder and has a hole in the center, and a portal-type that is fixed to both ends of the vibrator and stands up The machine frame and an upper mounting part fixed to the upper part of the machine frame so as to oppose the lower mounting part. The cylinder side mounting eye of the hydraulic shock absorber for measurement is placed on the mounting surface and the hydraulic pressure The piston rod of the shock absorber is fixed to the upper mounting portion through the hole, the hydraulic cylinder is contracted, and the rod side cylinder end of the hydraulic shock absorber is locked at the hole edge of the upper table. hydraulic shock absorber vibrating device, characterized in that 2. The vibration exciter for a hydraulic shock absorber according to claim 1, wherein a universal joint is provided in the upper mounting portion, and a tip end portion of the piston rod is fixed via the universal joint .

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