JPH0652223B2 - Pneumatic tire gripping rotation mechanism - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pneumatic tire gripping and rotating mechanism used in, for example, a tire testing machine.

2. Description of the Related Art Conventionally, in a tire testing machine such as a uniformity machine, a pneumatic tire is gripped from both sides by rims, filled with internal pressure, and then this tire is rotated around an axis to perform a test. As a gripping / rotating mechanism of a tire used in this case, for example, one described in Japanese Patent Publication No. 50-6922 is known. This one is
A drive shaft having a rim on which one bead portion of a pneumatic tire is seated; and a forward / backward shaft coaxial with the drive shaft having a rim on which the other bead portion of the pneumatic tire is seated, The shaft is driven and rotated by a motor, while the advancing / retreating shaft is moved up and down in the axial direction by a hydraulic cylinder mechanism to approach and separate from the drive shaft. The advancing / retreating shaft has a conical fitting protrusion that gradually narrows toward the tip, while the drive shaft has a conical fitting hole that gradually expands toward the tip. When performing the test, both bead portions of the pneumatic timer are seated on both rims and the advancing / retreating shaft is raised, and then the pneumatic tire is filled with the internal pressure. At this time, the fitting protrusion is fitted in the fitting hole to maintain the concentricity of the driving and advancing / retreating shafts with high accuracy, thereby ensuring high measurement accuracy.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in such a gripping and rotating mechanism of a pneumatic tire, when the pneumatic tire is filled with an internal pressure, a reaction force of this internal pressure (about 80 tons in a large tire) is generated. Since the driving and reciprocating shafts act in the direction of separating them from each other, the surface contact between the fitting protrusion and the fitting hole is released, and the concentricity of both shafts is likely to be reduced. Therefore, if an attempt is made to give a force that overcomes the reaction force of the internal pressure to the advancing / retreating shaft, there is a problem that the hydraulic cylinder mechanism becomes significantly large.

Means for Solving the Problems Such problems include a first member having a first rim on which one bead portion of a pneumatic tire is seated and a second rim on which the other bead portion is seated. The second member coaxial with the first member
A member, a rotation means for rotating one of the first and second members around its axis, and at least one of the first and second members in the axial direction to move them relatively close to each other. In a pneumatic tire gripping and rotating mechanism including: a contacting / separating unit that separates the first member, the first member has a taper body that widens toward the tip and has an outer periphery formed of a part of a conical surface. The two members can accommodate the taper body and have a taper hole that is tapered toward the tip and has an inner periphery formed of a part of a conical surface, and also has a slit that guides the taper body to the taper hole. be able to.

Action First, attach one bead portion of the pneumatic tire to the first rim,
With the other bead seated on the second rim, the first and second members are brought close to a predetermined position by the contacting / separating means. During this approach, the tapered body passes through the slit and is guided into the tapered hole. Next, by the rotating means, the first and second
The member is relatively rotated by a predetermined angle, and the outer circumference formed by a part of the conical surface of the taper body and the inner circumference formed by a part of the conical surface of the tapered hole face each other. Next, when the first and second members are separated by the contacting / separating means, the outer periphery of the tapered body and the inner periphery of the tapered hole are in surface contact with each other, and the concentricity of the first and second members is highly accurate. Retained. At this time, the outer circumference of the taper body widens toward the tip, while the inner circumference of the taper hole tapers toward the tip. The outer circumference of the tapered body can be pressed against, and as a result, the contacting / separating means does not need to output a force that overcomes the internal pressure,
The miniaturization of this can be achieved. Next, when one of the first and second members is rotated by the rotating means, the first and second members and the pneumatic tire rotate around the axis, and the test is performed in this state.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, reference numeral 1 denotes a horizontal roll conveyor, which extends perpendicularly to the paper surface and conveys a pneumatic tire 2 to be subjected to a uniformity test. Reference numeral 5 denotes a frame of a uniformity machine, and a case 6 fixed to the frame 5 has a vertical drive shaft 7 rotatably supported. A pulley 8 is fixed to the upper end of the drive shaft 7, while a motor 9 is attached to the frame 5. This motor 9
A belt 11 is stretched between the pulley 10 and the pulley 8 attached to the output shaft of the. 12 is the drive shaft 7
Is an encoder that is connected to and detects the rotational speed of the drive shaft 7. The encoder 12 controls the operation of the motor 9 based on the detection result. The pulleys 8 and 10, the motor 9 and the belt 11 described above collectively constitute a rotating means 13 for rotating a first member 26, which will be described later, around its axis. An intermediate shaft 16 is fixed to the lower end of the drive shaft 7, and a first rim 20 on which one bead portion 17 of the pneumatic tire 2 is seated is attached to the outer periphery of the intermediate shaft 16. A supply passage 18 and a plurality of intermediate passages 19 communicating with the supply passage 18 are formed in the drive shaft 7 and the intermediate shaft 16, respectively.
18 and the intermediate path 19 supply an internal pressure to the pneumatic tire 2 when the pneumatic tire 2 is mounted on the uniformity machine. As shown in FIGS. 1 and 3, the intermediate shaft 16 has a tapered body 21 at its tip (lower end), and the tapered body 21 has a substantially truncated cone shape that widens toward the tip. There is. A plurality (three in this embodiment) of arcuate recesses 22 are formed in the taper body 21 at equal intervals in the circumferential direction, and as a result, arcuate leg portions 23 are formed between the arcuate recesses 22. . The bottom surface of the arcuate recess 22 is formed of a part of the outer peripheral surface of the cylinder, and the outer circumference 24 of the leg portion 23 is formed of a part of the conical surface. Further, a plurality of pin holes 25 are formed on the tip end surface of the tapered body 21 at equal angles. The drive shaft 7, the intermediate shaft 16, and the first rim 20 described above collectively constitute the first member 26. Referring again to FIGS. 1 and 2, an elevating case 31 is movably supported on the frame 5 directly below the first member 26, and an advancing / retreating shaft 32 is rotatably supported on the upper part of the elevating case 31. This advance / retreat shaft 32 has a first rim
A second rim 34 is mounted coaxial with 20 on which the other bead portion 33 of the pneumatic tire 2 is seated. The reciprocating axis 3
2. The second rim 34 constitutes a second member 35 coaxial with the first member 26 as a whole. 36 is the piston rod 37 is the lifting case 31
The second member 35 is moved in the axial direction by the operation of the cylinder 36 so that the first member 26 and the second member 35 are relatively moved toward and away from each other. To be As shown in FIGS. 1 and 4, a taper hole 38 having a substantially truncated cone shape is formed at the tip (upper end) of the advancing / retreating shaft 32 as it goes toward the tip.
Further, a plurality of (three in this embodiment) arc-shaped slits 39 are formed on the advancing / retreating shaft 32 at equal angles in the circumferential direction,
The radially inner ends of these arcuate slits 39 communicate with the tapered holes 38, and the radially outer ends thereof form a part of the outer peripheral surface of the cylinder. As a result, arcuate protrusions 40 are formed between the arcuate slits 39 at equal angles in the circumferential direction, and the inner circumference 41 of each protrusion 40 has a conical surface with the same slope as the slope of the outer circumference 24 of the leg 23. It consists of a part of. Then, the first member 26 and the second member 35
When the two are close to each other, the leg portion 23 of the taper body 21 is guided to the arcuate slit 39 and is housed in the taper hole 38. Referring again to FIGS. 1 and 2, 46 is a cylinder attached to the lifting case 31, and a bearing 48 is attached to the tip of the piston rod 47 of the cylinder 46. 49 is a stop shaft whose rotation speed is detected by the encoder 50,
A lower end of the stop shaft 49 is rotatably supported by the bearing 48, and a flange body 51 is attached to the upper end thereof. A plurality of pins 52, which are respectively inserted into the pin holes 25, are attached to the flange body 51. A slide key 53 is interposed between the stop shaft 49 and the advancing / retreating shaft 32, which allows the stop shaft 49 and the advancing / retreating shaft 32 to move relative to each other in the axial direction, and these are integrated. Is rotated. Incidentally, 54 is a seal member for preventing the internal pressure filled in the pneumatic tire 2 from flowing out.
Pin hole 25, cylinder 46, stop shaft 49, flange body described above
When the outer circumference 24 of the first member 26 is in surface contact with the inner circumference 41 of the second member 35, the pins 51 and the pins 52 as a whole are the first and second members 26, 35.
The rotation stopping means 55 for preventing the relative rotation of the. Reference numeral 61 denotes a movable frame installed on the side of the first member 26. The movable frame 61 is supported by a horizontal rail 62 fixed to the frame 5 and moved by a driving means (not shown) to move the first member 26. Approach and separate from. A load wheel 63 is rotatably supported by a movable frame 61 via a load cell 62, and the load wheel 63 is a first and a second rim 20,
It is possible to contact the tread surface of the pneumatic tire 2 mounted on the 34.

Next, the operation of the embodiment of the present invention will be described.

First, the pneumatic tire 2 laterally placed by the roll conveyor 1 is conveyed to just above the second member 35. next,
The piston rod 37 of the cylinder 36 is projected to raise and lower the case 31
To raise the bead 33 of the pneumatic tire 2 to the second rim.
Seat 34. When the elevating case 31 is further raised in this state, the leg portions 23 of the taper body 21 are inserted into the taper hole 38 after passing through the arcuate slits 39. During this insertion, the bead portion 17 of the pneumatic tire 2 is seated on the first rim 20, so that the pneumatic tire 2 has the first portion.
It is mounted on the rim 20 and the second rim 34. And the leg portion 23
When the advancing / retreating shaft 32 is lifted to such an extent that a slight gap is formed between the outer circumference 24 and the inner circumference 41 of the protrusion 40, the operation of the cylinder 36 is stopped. Next, the motor 9 is activated and the first member 26
Rotates by a predetermined angle (60 degrees in this embodiment). At this time, since the encoder 12 controls the operation of the motor 9 while detecting the rotation angle, highly accurate rotation control is performed. As a result, the outer circumference 24 of the leg portion 23, which has been opposed to the bottom surface of the arcuate slit 39, is opposed to the inner circumference 41 of the protrusion 40. Next, when the piston rod 37 of the cylinder 36 is slightly retracted, the outer circumference 24 of the tapered body 21 and the inner circumference 41 of the tapered hole 38 come into surface contact with each other.
Since 41 is composed of a part of a conical surface having the same gradient, the first member 26 and the second member 35 are aligned with high concentricity. Next, the piston rod 47 of the cylinder 46 is projected to move the stop shaft 49 in the axial direction toward the taper body 21,
Insert the pins 52 into the pin holes 25, respectively. This allows
The relative rotation between the first member 26 and the second member 35 is prevented. Next, the pneumatic tire 2 is filled with a specified internal pressure through the supply passage 18 and the intermediate passage 19. When the pneumatic tire 2 is filled with the internal pressure in this manner, the internal pressure causes the first member 26 and the second member
A force for separating them acts on the member 35, and this force is applied to the outer circumference 24 of the tapered body 21 and the inner circumference 41 of the tapered hole 38.
The contact surface pressure with and is increased so that the concentricity does not decrease even if some external load is applied. Next, the movable frame 61 is brought close to the pneumatic tire 2, and the road wheel 63 is pressed against the tread portion of the pneumatic tire 2 at a specified pressure. When the motor 9 is rotated in this state, the first member 26, the second member 35, and the pneumatic tire 2 rotate integrally. At this time, longitudinal and lateral force fluctuations acting on the road wheel 63 are detected by the load cell 62, and the uniformity of the pneumatic tire 2 is measured.
Further, at this time, since the outer circumference 24 and the inner circumference 41 are in surface contact with a large contact pressure due to the internal pressure in the pneumatic tire 2,
The frictional resistance between the intermediate shaft 16 and the advancing / retreating shaft 32 increases, and as a result, relative rotation between the first member 26 and the second member 35 is prevented. Moreover, in this embodiment, the first member 26 and the second member 35 are
Since they are connected to each other by the rotation stopping means 55, the relative rotation of the first and second members 26 and 35 is reliably prevented even if a rotational force is applied only to the first member 26. In addition, this detent means
When 55 is damaged and a circumferential slip occurs between the first member 26 and the second member 35, the signal from the encoder 12 and the signal from the encoder 50 have different values. I try to give an alarm.

In addition, in the above-mentioned embodiment, the case where the first member 26 is rotated by the rotating means 13 has been described, but in the present invention, the second member 35 may be rotated. Further, in the present invention, only the first member may be moved by the contacting / separating means, or both the first and second members may be moved. Further, in the present invention, the outer circumference and the inner circumference of the tapered body and the tapered hole may be formed by a part of a polygonal pyramid surface, for example, a hexagonal pyramid surface or an octagonal pyramid surface. Further, in the present invention, flat slopes or steps are formed on the outer circumference and the inner circumference of the tapered body and the tapered hole, respectively, and these slopes or steps are engaged with each other so that
You may stop rotation of a 2nd member.

EFFECTS OF THE INVENTION As described above, according to the present invention, it is possible to align the rim holding the tire with high concentricity even if the contacting / separating means is downsized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front sectional view showing an embodiment of the present invention, FIG. 2 is a schematic front view thereof, FIG. 3 is a bottom view of an intermediate shaft, and FIG.
The figure is a plan view of the advancing / retreating axis. 2 ... Pneumatic tire, 13 ... Rotating means 17, 33 ... Bead portion, 20 ... First rim 21 ... Tapered body, 26 ... First member 34 ... Second rim, 35 ... Second Member 36 …… Cylinder (contact / separation means) 38 …… Tapered hole 39 …… Slit (arc slit)

Claims (1)

[Claims] 1. A first member having a first rim on which one bead portion of a pneumatic tire is seated and a second rim on which the other bead portion is seated, and a second member coaxial with the first member. When,
Rotating means for rotating either one of the first and second members around its axis, and contact means for moving at least one of the first and second members in the axial direction so as to relatively approach and separate them. In the pneumatic tire gripping and rotating mechanism including a separating means, the first member has a taper body that widens toward the tip and has an outer periphery formed of a part of a conical surface, while the second member is The air-filled structure is capable of accommodating the taper body and has a taper hole which is tapered toward the tip and has an inner circumference formed of a part of a conical surface, and a slit for guiding the taper body to the taper hole. Tire grip rotation mechanism.