JP4434915B2 - Method and apparatus for measuring tire uniformity - Google Patents

Description

  The present invention measures various uniformity of tires, for example, radial force variation (hereinafter referred to as “RFV”), lateral force variation (hereinafter referred to as “LFV”), lateral force deviation (hereinafter referred to as “LFD”) and coni The present invention relates to a tire uniformity measuring method suitable for use in measuring at least one kind of non-uniformity such as a city force (hereinafter referred to as “COF”) and a uniformity measuring apparatus used therefor.

As a conventional tire uniformity measuring device, as disclosed in Patent Document 1, for example, a tire is held between an upper chuck and a lower chuck that are both displaced up and down, and the tire is filled with internal pressure. An apparatus is known that measures various types of runout of a tire by applying a pressing force to the tread circumferential surface of the tire with a load roll below.
However, in such a conventional technique, there is a disadvantage that the moving mechanism of the upper chuck and the lower chuck particularly makes the apparatus large.

Therefore, in recent years, as disclosed in Patent Document 2, in addition to downsizing the measuring device, the purpose is to perform more accurate measurement under a form closer to the actual use state of the tire. In addition, a tire filled with air pressure by being mounted on a wheel rim is supported in a horizontal posture by a rotary chuck, and a driving roller connected to a driving motor is pressed against the peripheral surface of the tire with a required force. In this method, the RFV is determined by measuring the variation of the reaction force in the radial direction of the tire. According to this device, the uniformity as the total performance combining the characteristics of the tire and the rim is detected. There are benefits to get.
JP-A-57-84328 JP 2001-341507 A

  However, in this proposed technique, for example, as schematically shown in FIG. 4, a horizontal pressing force of a size of up to 10 kN is applied to the tire T supported at the tip of the rotary chuck C by the driving roller R. When this is applied, there is a high risk that the tire T will behave and come out of the chuck C, and that the wheel rim Wr and the wheel disc Wd will be bent and deformed. In order to force a change in the relative posture with respect to the tire T, there has been a problem that a required squareness and / or parallelism may be distorted, resulting in a decrease in uniformity measurement accuracy.

  The present invention has been made to solve such problems of the proposed technology, and its object is to sufficiently suppress the above-described behavior and deformation of the rim-assembled tire. Accordingly, it is an object of the present invention to provide a tire uniformity measuring method and apparatus capable of measuring uniformity with high accuracy while downsizing the measuring apparatus.

In the tire uniformity measuring method of the present invention, a tire mounted on a wheel rim and filled with air pressure is driven by a spindle, for example, a horizontal posture in which the central axis is directed in the vertical direction, or a vertical posture in which the central axis is directed in the horizontal direction. in addition to rotatably support the circumferential surface of the tire, the load roll, for example by pressing in a horizontal position or vertical position, hitting the measuring the required force to be generated under the rotation of the tire, pressing A lowering means that includes a rod, a lifting frame that rotatably supports the pressing rod, a housing that houses the lifting frame, and a cylinder that is connected to the lifting frame; in addition, by raising and lowering displaced independently the push rod relative to said housing with said cylinder, Ear and in the measurement of the force while pressing for example via the wheel disc to the spindle side.

  Here, it is preferable that the “wheel rim” has a rim contour defined in the following standards, and “air pressure” here is defined in accordance with the maximum load capacity in the following standards. Air pressure can be used. “Maximum load capacity” means the maximum mass allowed to be loaded on a tire according to the following standards.

  The standard is determined by an industrial standard effective in the region where the tire is produced or used. For example, in the United States, “THE TIRE AND RIM ASSOCIATION INC. YEAR BOOK” is used. It is “STANDARDS MANUAL” of European Tire and Rim Technical Organization, and “JAMATY YEAR BOOK” of the Japan Automobile Tire Association in Japan.

The tire uniformity measuring apparatus according to the present invention is a tire that is configured for uniformity measurement or is mounted on a wheel rim that can also be used for mounting on an actual vehicle, and a tire filled with air pressure is directly connected to a wheel disc. Alternatively, a spindle that can rotate freely in a horizontal position under indirect fitting is provided, and a load roll that is pressed against the peripheral surface of the tire with a required force is moved in a horizontal position and moved forward and backward with respect to the tire. In addition, it is arranged on the load roll side, for example, the central axis of the load roll, and a means for measuring the force in the required direction generated based on the rotation of the tire is arranged. , for example, under direct or indirect engagement with the wheel disc state, and are not provided with pressure means for pressing the tire to the spindle side, piezoelectric under A step, a pressure rod, a lifting frame that rotatably supports the pressure rod, a housing that houses the lifting frame, and a pressure frame that is connected to the lifting frame and is independent of the housing together with the lifting frame. And a cylinder that is displaced up and down .

  In the method of the present invention, a rim-assembled tire is rotatably supported by a spindle, and a load roll is pressed against a peripheral surface of the tire with a required force to generate a force generated based on the rotation of the tire. As with the previously proposed technology, RFV, LFV, LFD as a more realistic overall performance that combines the characteristics of tires and rims with a small device. , COF and others.

Moreover Here, the tire using the pressure means hitting the measurement of such forces to press the spindle side, of the tire, by increasing the restraining force for the spindle, the tire to the spindle fixed more firmly Therefore, it effectively prevents the tire from coming out of the spindle against the tire pressing force by the load roll, and flexure deformation of the wheel rim and the disk, effectively preventing an unexpected decrease in uniformity measurement accuracy. be able to.

  And the above-mentioned fluctuation component as the overall performance can be measured with higher accuracy when the uniformity is measured by assembling the tire to the wheel rim having the rim contour defined in the standard. This is particularly remarkable when a wheel rim that can be used for mounting on an actual vehicle is applied.

  When this uniformity measurement is performed using a wheel rim for mounting on an actual vehicle, it is usually necessary to attach an adapter or the like that can be set to the uniformity measurement device to the wheel disc. On the other hand, when using a wheel rim configured exclusively for uniformity measurement, it is not necessary to attach an adapter or the like afterwards by pre-configuring the wheel disc part with a fitting part to the measuring device and other set parts. It becomes.

  Further, in the apparatus of the present invention, the tire assembled to the wheel rim is rotatably supported under the support of the wheel disk by the spindle, and the wheel disk is pressed against the spindle by the rolling means to restrain the tire there. In the state, the load roll is pressed against the circumferential surface of the tire with the required force, the tire is rotated at the required speed, and the required direction generated based on the rotation of the tire by the measuring means provided on the load roll side. By measuring the force, it is possible to carry out the method according to the present invention reliably and always appropriately.

FIG. 1 is a schematic front view showing a part of an embodiment of the apparatus according to the present invention as a cross section.
In the figure, reference numeral 1 denotes a tire. The illustrated tire 1 is mounted on a wheel rim 2 that can also be used for mounting on an actual vehicle, and is filled with air pressure having a magnitude as required.

  A wheel disc 3 that functions as a mounting portion of the tire to the axle hub is integrally provided on the inner peripheral side of the wheel rim 2. Here, the tire 1 is required for the test apparatus via the wheel disc 3. In order to enable the setting, the adapters 4 and 5 are attached to the front and back surfaces, in the figure, the upper and lower surfaces, for example, using bolt holes provided in the wheel disk 3.

And, in this illustrated example, the upper surface side adapter 4, the frustoconical depressions observed 8 to allow just the entry of push rod 7 of the draft means 6 to be described later is formed, the adapter 5 on the lower surface side, A frustoconical protrusion 10 is provided for its own insertion into the spindle 9.

Here, the spindle 9 that rotatably supports the tire 1 that is assembled to the wheel rim 2 and filled with air pressure in a horizontal posture as shown in the drawing is supported on the base member 12 by the bearing 11 and is rotated on the base member 12. 5 is formed at the upper end portion of the frustoconical recess 13 with the center axis being vertical, preferably allowing the projection 10 to be fitted exactly. A fixing means (not shown) that engages with a specific portion of the portion 10 and retracts and fixes the protruding portion 10 is provided.
According to this, the tire 1 is horizontally supported on the spindle 9 via the adapter 5 of the wheel disc 3 and can rotate together with the spindle 9.

By the way, in this case, when the horizontal flange 14 as shown in the figure provided on the lower surface side adapter 5 is brought into surface contact with the upper end of the spindle 9 to support the tire 1 and the wheel disc 3 directly, The support of the tire 1 by the spindle 9 can be made more stable,
This is the same when the rim flange of the wheel rim 2 is brought into surface or line contact with the upper end of the spindle 9 instead of the horizontal flange 14.

Further, as shown in this figure, by the rotational drive of the vertical male screw member 16 based on the operation of the motor 15, the female screw member 18 that is screwed into the male screw member 16 and attached to the slider 17 is moved up and down, whereby the reducing means 6 as well as the lifting frame 17 and the connecting rod 19 can be displaced up and down as expected in the vertical direction. At the same time, the pressure rod 7 of the rolling-down means 6 is moved up and down independently with respect to the housing 21 with the cylinder 20 provided on the rolling-down means itself, so that the tip of the pressing rod 7 is moved to the upper surface. it can be pushed to the side adapter 4 to the depression seen in the 8 at the required power.

  Here, the pressing rod 7 can rotate integrally with the tire 1 and the upper surface side adapter 4 by supporting the pressing rod 7 on the lifting frame 22 driven by the cylinder 20.

Note that the lifting frame 22 connected to the cylinder 20 is housed in the housing 21 via a linear guide or other guiding means, so that the frame 22 can be smoothly moved up and down and the lifting frame 22 is prevented from rotating. It is necessary to do .

  Moreover, the rolling-down means 6 can bring about an excellent raising / lowering position accuracy by displacing it with respect to the fixed side members 24, 25 under the action of the pair of sliders 17, 23.

Further, in the figure, reference numeral 26 denotes a steel load roll, for example, which is disposed in a horizontal posture with the central axis oriented in the vertical direction. This load roll 26 is displaced forward and backward horizontally with respect to the peripheral surface of the tire 1. The tire is pressed against the tire circumferential surface with a required force, and is rotated by a motor or the like (not shown).
Here, instead of rotationally driving the load roll 26, the spindle 9 can be rotationally driven while the load roll 26 can be a free roll.

  When such a load roll 26 is pressed against the circumferential surface of the tire and the tire 1 is rotated at a required speed based on its rotational drive, forces in various directions are generated based on the rotational movement of the tire 1. In this case, for example, a measuring means 27 such as a load cell capable of measuring at least one force in a predetermined direction is disposed on the central axis of the load roll 6.

  For uniformity measurement using the apparatus constructed as described above, the tire 1 assembled to the wheel rim 2 and filled with the required air pressure is used as shown in FIG. In the fitted state in the recess 13, the protrusion 10 is preferably fixed in the recess 13 and positioned in a horizontal position on the spindle 9, while under the action of the motor 15 and the cylinder 2, the reduction means 6 and Each of the pressing rods 7 is moved down and displaced, and the tip of the pressing rod 7 is pushed into the recess 8 of the upper surface side adapter 4 with a required force, so that the wheel disk 3 and thus the tire 1 is sufficiently strong to the spindle 9. Then, the load roll 26 is horizontally pressed with a required force on the tire circumferential surface and the load roll 26 is rotationally driven at a required timing. The required force including the reaction force generated in the tire 1 rotated by the load roll 26 can be measured by the measuring means 27. In such uniformity measurement, the tire 1 is a rolling means. Under the action of 6, it is fixed sufficiently firmly to the spindle 9, so that there is a risk of the tire 1 coming out of the spindle 9 and the deformation of the wheel rim 2 and the disk 3 as described with reference to FIG. 4. As a result, it is possible to achieve excellent uniformity measurement accuracy.

  FIG. 2 is a main part schematic diagram illustrating another lifting drive mechanism of the rolling-down means. FIG. 2A shows a pair of female screw members provided with a lifting frame 31 of the rolling-down means 6. 32, each male screw member 33 is screwed together, both male screw members 33 can be rotated synchronously by one motor 34 and timing belt 35, and the pressure rod 7 is provided by a cylinder 36 provided on the lifting frame 31. The lift frame 31 can be moved up and down.

  According to this configuration, the pressing rod 7 is displaced up and down by each of the motor 34 and the cylinder 36. Therefore, as in the case shown in FIG. 1, the positioning is easy and the pushing force can be adjusted. In addition to this, there is also an advantage that the working efficiency can be increased by reducing the stroke amount of the pressing rod 7.

In the drive mechanism shown in FIG. 2B, the pressing rod 7 is integrally formed with the lifting frame 31, and each of the pair of female screw members 32 provided on the lifting frame 31 is replaced with a motor 34 and a timing belt 35. Are screwed into a pair of male screw members 33 that are rotated in synchronization with each other.
Here, since the pressing rod 7 is displaced up and down only by the action of the motor 34, the positioning of the rod 7 becomes easy.

In the configuration shown in FIG. 2C, the pressing rod 7 of the rolling-down means 6 can be moved up and down over a required stroke only by the cylinder 37 attached to the fixed member.
In the figure, reference numeral 38 denotes a bearing that rotatably supports the pressing rod 7 on the cylinder rod.
Although not shown, it is preferable that such a bearing is also applied to those shown in FIGS. 2 (a) and 2 (b).

  According to this configuration, it is possible to adjust the pushing force of the pressing rod 7 as required under the action of the cylinder 37.

FIG. 3 is a main part schematic diagram illustrating a lifting guide mechanism of the rolling-down means.
FIG. 3A shows a structure in which the lifting frame 31 integrally formed with the pressing rod 7 is slidable with respect to the stationary member 39 via a linear guide 40. The guide shown in FIG. The mechanism guides the displacement of the rolling-down means 6 by a guide rod 41 provided so as to penetrate the lifting frame 31.

  FIG. 3C shows a pair of sliding rods 42 provided on the elevating frame 31 that pass through a bush 44 attached to the fixed side member 43 and are slidably contacted therewith, and FIG. Is provided with a bush 45 for guiding the displacement of the pressing rod 7 when the pressing rod 7 can be moved up and down with respect to the lifting frame 31 as shown in FIG. It is.

It is an approximate line front view showing an embodiment of an apparatus concerning this invention in part as a section. It is a principal part schematic diagram which illustrates the other raising / lowering drive mechanism of a rolling-down means. It is a principal part schematic diagram which illustrates the raising / lowering guide mechanism of a rolling-down means. It is a basic diagram which shows the problem of proposed technology.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tire 2 Wheel rim 3 Wheel disk 4, 5 Adapter 6 Reduction means 7 Press rod 8, 13 Indentation 9 Spindle 10 Protrusion 11 Bearing 12 Base member 14 Horizontal flange 15, 34 Motor 16, 33 Male screw member 17, 23 Slider 18, 32 Female thread member 19 Connecting rod 20, 36, 37 Cylinder 21 Housing 22, 31 Lifting frame 24, 25, 39, 43 Fixed side member 26 Load roll 27 Measuring means 35 Timing belt 38 Bearing 40 Linear motion guide 41 Guide rod 42 Sliding Rod 44, 45 bush

Claims (2)

A tire mounted on a wheel rim and filled with air pressure is rotatably supported by a spindle, and a load roll is pressed against the peripheral surface of the tire to measure a force in a required direction generated under the rotation of the tire. When measuring tire uniformity,
Displacement of the pressing means comprising a pressing rod, a lifting frame that rotatably supports the pressing rod, a housing that houses the lifting frame, and a cylinder coupled to the lifting frame, with respect to the wheel disk. In addition, a tire uniformity measuring method for measuring force while pressing the tire toward the spindle side by moving the pressing rod up and down independently of the housing together with the lifting frame with the cylinder . A spindle that supports a tire filled with air pressure by being mounted on a wheel rim in a horizontal posture while being fitted with a wheel disc is provided, and a load roll that is pressed with a required force on the circumferential surface of the tire is provided. In addition to being placed in a horizontal position, a measuring means for the force in the required direction generated based on the rotation of the tire is installed on the load roll side, and it is displaced up and down with respect to the wheel disc, and the tire is pressed toward the spindle side. Ri Na provided reduction means for the piezoelectric under unit, push rod and, a lifting frame for rotatably bearing supporting the pressing pressure rod, and a housing for accommodating the elevating frame, said push rod being connected to the lifting frame A tire uniformity measuring device comprising a cylinder that moves up and down independently of the housing together with the lifting frame .

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