JPH0439528Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a tire inner diameter measuring device, and particularly to a device having a bead contact mechanism on a scroll chuck.

2. Description of the Related Art When performing a balance test using a tire balance tester, it is necessary to measure the inner diameter of the tire to be subjected to the balance tester in advance using a tire inner diameter measuring device.

The conventional tire inner diameter measuring device centers the tire that has been conveyed by a roller conveyor using a centering roller, then inserts an inner diameter detection rod into the inner diameter of the tire, and after inserting this inner diameter detection rod, the inner diameter detection rod is inserted into an air cylinder. When the inner diameter detection rod is pressed against the tire bead and the reaction force of the bead and cylinder pressing force are balanced, the inner diameter detection rod stops. The inner diameter of the tire is measured by measuring the stopped point using the output voltage of a differential transformer connected to a detection rod.

Problems that the invention aims to solve However, tires are manufactured in random conditions on the tire manufacturing line. Furthermore, the sizes of tires manufactured vary widely, and the hardness of the rubber used to make tires also varies from hard to soft. Therefore, in the measuring device, it is necessary to consider that the hardness of the rubber, that is, the reaction force of the tire bead, changes over time.

That is, even if the pressing force of the cylinder can be kept constant, the measured value of the inner diameter may not necessarily indicate the actual inner diameter of the tire due to differences in the reaction force of the tire bead. For example, if you have a tire with an inner diameter of 13", the measured value is displayed as a radius, so it should be 6.5", but for the reason mentioned above, it may actually be output as 7.1".
In this case, the inner diameter of the tire is 14.2'', that is, there is a risk that the tire will be determined to be a 14'' tire.

This idea was made in view of the above circumstances, and it is a tire inner diameter measuring device that can accurately measure the inner diameter even if there are differences in rubber hardness, that is, differences in tire bead reaction force. is intended to provide.

Means for Solving the Problems The tire inner diameter measuring device according to this invention includes a scroll chuck driven by a motor, a bead contact mechanism attached to the scroll chuck, and an arm constituting the bead contact mechanism. arm movement distance detection means for detecting a movement distance of the bead contact mechanism, the bead contact mechanism is arranged radially, the tips thereof are on the same circumference, and the bead contact mechanism is slid in a radially expanding direction by the motor. A plurality of the arms, a split rim hinged to the outside of the arm, an elastic member interposed between the arm and the split rim to resiliently bias the split rim in a diametrical direction, and the arm and the split rim. A split rim contact detection means is provided between the arms and detects that the split rim has contacted the tire bead, and the split rim is hinged at the tip of the arm.

Operation When all of the plurality of split rims come into contact with the tire bead, the contact is detected by the bead contact mechanism, and then the operation of the motor is stopped, and the plurality of split rims constituting the arm movement distance detection means at that point are detected by the bead contact mechanism. detects which of the proximity switches is turned on.

Embodiment FIG. 1A is a partially omitted front view of an embodiment of this invention, and FIG. 1B is a partially sectional view taken along line A--A in FIG. 1A.

In the figure, 10 is a scroll chuck, 20
30 is a geared motor (hereinafter simply referred to as motor) that drives the scroll chuck 10, and 30 is a motor 2.
40 is a bead contact mechanism that slides in the diametrical direction by the operation of the scroll chuck 10, and 50 is a cylinder mechanism that slides the scroll chuck 10 side in the forward direction, that is, in the direction of insertion into the tire. , 60 is arm movement distance detection means for detecting the movement distance of the arm. Note that B indicates a cross section of the tire bead.

As shown, the scroll chuck 10 includes a chuck portion 11 formed in half and a chuck plate 12 for fixing the chuck portion 11.

The bead contact mechanism 40 includes three arms 41 slidably provided radially on the chuck portion 11, a split rim 42 hinged at the tip of the arms 41, and a split rim 42 interposed between the arms 41 and the split rim 42. a spring 43 that elastically biases the split rim 42 in the direction of expanding its diameter; and a split rim contact that is provided between the arm 41 and the split rim 42 and detects that the split rim 42 has contacted the tire bead B. detection means 44. And the arm 41
are arranged so that their tips are located on the same circumference. Here, the split rim contact detection means 44
is composed of a proximity switch 441 provided on the arm 41 side and a proximity body 442 provided on the split rim 42 side corresponding to the proximity switch 441. However, in this design, the proximity switch 441 is replaced by the split rim 4.
On the second side, the proximate body 442 may be provided on the arm 41 side. In addition, 45 is a stopper, and the protruding length of this stopper 45 is set so that when it comes into contact with the back side of the split rim 42, the proximity switch 441 is turned on.

The arm movement distance detection means 60 includes a proximity body 61 attached to the rear end surface of the arm 41 and a plurality of proximity switches 62A, 62B, 62C, 6 attached to a plate 121 fixed to the chuck plate 12.
It is composed of 2D. However, the proximity body 61 is located on the chuck plate 12 side, and the proximity switch 62 is
A, 62B, 62C, and 62D may be provided on the plate 121 side.

The proximity switches 62A, 62B, 62C, 6
The mounting position of 2D is, for example, when viewed from the center of the shaft.
6″ (12″ tire), 6.5″ (13″ tire), 7.0″ (14″
'' tire) and 7.5''(15'' tire).Here, the proximity body 61 is approximately L-shaped, and its tips, that is, proximity switches 62A, 62B, 62
The portions that come into contact with C and 62D are tapered, and the tip portions are formed flat by a width δ. This width δ is set to be smaller than at least half the mutual spacing between adjacent proximity switches 62.

The cylinder mechanism 50 includes a cylinder 51, a plate 52 that fixes the cylinder 51 to the frame side of a roller conveyor (not shown), a guide rod 53 that is fixed to the chuck plate 12, and a guide cylinder 54 that is fixed to the plate 52 side. Equipped with: The cylinder 51 and the chuck plate 12 are connected by a cylinder rod 55. However, if the tires conveyed by the roller conveyor are to be moved toward the split rim contact detection means 44, the cylinder mechanism 50 is not necessarily required.

The operation of the embodiment configured as described above will be explained below.

Tires are conveyed in a random manner from a roller conveyor (not shown), and are positioned and fixed by a centering roller (not shown).

The cylinder rod 5 is moved by the operation of the cylinder 51.
5 moves forward in the right direction in the figure and inserts the bead contact mechanism 40 into the inner diameter of the tire. At this point, the split rim 42 is opened in the diametrical direction by the spring 43.

As the motor 20 operates, the arm 41 slides in the direction of diameter expansion.

As the arm 41 slides, one of the three split rims 42 comes into contact with the tire bead, and then the remaining split rims 42 come into contact with the tire bead. As described above, this contact is detected by turning on the proximity switch 441.

When all three proximity switches 441 are turned on, the motor 20 stops rotating. At this point, the proximity switches 62A, 62B,
It is detected whether 62C or 62D is in the on state.

When the tire proximity switch 62A is on,
The inner diameter of the tire is determined to be 12″.

Effects of the invention The tire inner diameter measuring device of this invention detects the contact with a proximity switch when all of the plurality of split rims contact the tire bead, then stops the motor operation, and measures the tire diameter at that point. Since it is configured to detect which of the proximity switches etc. is turned on, even if there is a difference in the hardness of the tire rubber, that is, a difference in the reaction force of the tire bead, it is possible to accurately detect the inner diameter of the tire. can be measured.

[Brief explanation of drawings]

FIG. 1A is a partially omitted front view of an embodiment of this invention, and FIG. 1B is a sectional view taken along the line A--A in FIG. 1A. 10...Scroll chuck, 20...Motor, 30...Reducer, 40...Bead contact mechanism,
50...Cylinder mechanism, 60...Arm movement distance detection means, 41...Arm, 42...Split rim, 4
4... Split rim contact detection means.

Claims (1)

[Scope of utility model registration request] It is equipped with a scroll chuck driven by a motor, a bead contact mechanism attached to the scroll chuck, and arm movement distance detection means for detecting a movement distance of an arm constituting the bead contact mechanism, The bead contact mechanism is
They are arranged radially and their tips are on the same circumference,
and a plurality of arms that slide in the diametrically expanding direction by the motor, a split rim that is hinged to the outside of the arm, and a split rim that is interposed between the arms and the split rim and that elastically pushes the split rims in the diametrically expanding direction. It has an elastic member that biases the arm, and a split rim contact detection means that is provided between the arm and the split rim and detects that the split rim has contacted the tire bead, and the split rim is hinged at the tip of the arm. A tire inner diameter measuring device characterized in that: