JPH0253601A - Center measurement method for hub - Google Patents

Abstract

PURPOSE:To simply and accurately measure the pre-positioned center position of a hub by mounting a plurality of measuring pieces attached to a robot which makes contact with the upper, lower and side parts of the external round face of a hub, and a plurality of measuring units which measure the quantity of displacement of each of the measuring pieces. CONSTITUTION:A robot with tyres has a head 33 which is able to be moved in the horizontal X- and Y-axis directions and the vertical Z-axis direction and able to be turned in the direction of the C shaft turning through the Z-axis, and this head 33 has both a measuring and positioning part 35 and tyre mounting part 37. Upper and lower slides 63 and 65 are approached to each other until measuring pieces 75 and 77 make contact with a hub, and the center of the measuring and positioning part 35 with the vertical relation to the output of the linear measuring units 81 and 83, the quantity of displacement of the center of the hub and the external diameter of the hub are measured. With the measuring piece 79 of a left slider 67 in contact with the hub, the quantities of displacement in both the center of the measuring and positioning part 35 in the horizontal position and the center position of the hub are measured according to the output of a linear measuring unit 85 and the external diameter of the hub. Based on each of measurement results, the centers of both the measuring and positioning part 35 and the hub are coincided with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an apparatus for automatically mounting tires in an automobile assembly process.

<Prior Art and Problems to be Solved by the Invention> In order to automate the assembly of automobiles, a device for automatically attaching tires to the hub of the automobile is required.

This type of automatic tire mounting device is equipped with a robot that positions the tire on the hub of a car and tightens the nut, a nut supply device that supplies the nut to the robot, and a tire supply device that supplies the tire. . In this case, the hub of the vehicle must be in place in order for the robot to position the tire on the hub and screw the nut onto the hub bolt.

Generally, on an assembly line, automobiles are placed on a shuttle and transported, and the hub is positioned in a tire mounting pit by pushing up the lower arm of the suspension from below using a lift device. However, even if the lift device pushes up a certain amount, differences in car models and individual differences,
Due to steering angles, etc., the hubs will not necessarily be in the same position, and as a result, it is expected that the robot will not be able to attach the tires to the hubs.

The present invention has been made in view of these points,
The object of the present invention is to provide a device for measuring the center position of a hub that has been positioned in advance, and is intended to position a robot based on the measurement results.

Means for Solving the Problems> A hub center according to the present invention to achieve the above objects.
In an automatic tire mounting device equipped with a robot for positioning a tire on the hub of an automobile and tightening a nut, the window device is mounted on the robot so as to be movable in the vertical direction. first and second measuring pieces that contact the upper and lower parts of the circular outer circumferential surface; and a third measuring piece that is attached to the robot so as to be movable laterally and that contacts the side of the circular outer circumferential surface of the hub. , and a length measuring device for measuring the amount of displacement of each measurement piece.

Further, in a hub in which an even number of hub bolts are arranged equidistantly in the circumferential direction, the measurement piece may be brought into contact with the outer circumferential surface of the hub bolt.

Action〉 The first and second measurement pieces are brought into contact with the circular outer peripheral surface of the hub,
From the outputs of these length measuring devices, the amount of displacement of the center of the hub relative to the center on the robot side in the vertical direction and the diameter of the circular outer peripheral surface of the hub are determined. Next, the third measuring piece is brought into contact with the circular outer circumferential surface of the hub, and the center of the stone hub relative to the center of the spout/pot side in the lateral direction is determined from the output of the length measuring device and the diameter of the hub determined previously. Find the amount of displacement.

Furthermore, when the number of hub bolts is even, the center of the hub can be measured in the same manner as described above by bringing the measurement piece into contact with the hub bolts.

Embodiment Hereinafter, an embodiment of the present invention will be specifically described with reference to the drawings.

First, an outline of an automatic tire mounting device according to an embodiment of the present invention will be explained with reference to FIG. 6, which is a plan view thereof. As shown in Figure 6, this device has four automatic tire mounting devices [1
1, these four automatic tire mounting devices 11 are installed in the assembly line, and the front and rear left tires are mounted in the first pit 13, which is flooded, and the front and rear tires are mounted in the second bit 15. Arrange it so that the right tire is installed.

The reason why the diagonally located tires are mounted at the same time is to avoid problems caused by interlocking of the left and right hubs during tire mounting.

Each tire automatic mounting device 11 includes a tire mounting robot 17
, Nut Feeder 19, Nut Loader 21. Nutto robot 23, tire supply device 25, etc. are being developed. Nut feeder 19 is handled on this assembly line 68! It has six nut storage units 27 each storing different types of nuts according to the number of nuts, and supplies all of them to a predetermined delivery position 29.

The pear rope 21 supplies the necessary number of nuts for mounting one tire to the hub to the tire mounting 50 bolts 17 at once. It has a pedestal 31 having a support part.

This pedestal 31 has four nut support parts and one for five nuts.
There are two types of five-pin nuts with two nut support parts, which can be used depending on the type of car. Further, the nut robot 23 grabs nuts at the delivery position 29 of the nut feeder 19 and places the required number of nuts on the pedestal 31 of the nut loader 21. On the other hand, the tire supply device 25 supplies tires carried in from a conveyor (not shown) to the tire mounting robot 17 in a predetermined direction.

The tire mounting robot 17 moves in the horizontal XY axis direction and the vertical Z direction.
It has a head 33 that is movable in the axial direction and rotatable in the C-axis direction around the Z-axis, and this head 33 is provided with a measurement/positioning section 35 and a tire mounting section 37. The measurement/positioning section 35 and the tire mounting section 37 are of the 2n type for four tires and for five tires, and are arranged on opposite sides, similar to the above-mentioned pedestal 31. The measurement/positioning unit 35 measures the center of the hub in order to center the tire mounting robot 17, and rotationally positions the hub so that the hub bolt is at a predetermined position.

Further, the tire mounting portion 37 has a plurality of nut runners (not shown) in the center thereof in the same relative positional relationship as the hub bolts, and has tire gripping claws 39 around the outer periphery thereof.

In such a device, the car body is used as a positioning device when installing tires! The hub is positioned at a predetermined position at 41, and the hub is positioned by pushing up the four arms of the suspension using a lift device 43. After the tire mounting robot 17 receives a nut from the nut loader 21 into the nut runner of its tire mounting section 37, it directly faces the tire supply device 25 and grips the tire with its tire gripping claws 39. Next, the tire mounting robot 17 is placed with the measurement/positioning unit 35 directly facing the hub.
Then, the head 33 is rotated 90" so that the tire mounting part 37 faces the hub, and the tire is pressed against the hub and the nut is screwed into the hub bolt to install the tire. conduct.

Next, the measurement/positioning section 35 provided in the above-mentioned head 33 will be explained in detail. As mentioned above, there are two types of measurement/positioning section 35, one for four lines and one for five lines, but the one for five lines will be explained here.

FIG. 1 is a front view of this measurement/positioning section 35, FIG. 2 is a side view thereof, FIG. 3 is a plan view thereof, and FIG.
It/-IV sectional view in the figure, and FIG. 5 is an enlarged sectional view of the probe portion.

As shown in FIGS. 1 to 5, the measurement/positioning section 35 includes a support frame 45 having a box-shaped cross-sectional structure.
is mounted on a substrate 47 attached to the head 33. The support frame 45 is supported by the base plate 47 via a linear guide 49 so as to be slidable in the front and back direction, and is normally urged forward by a spring 51 and a stopper fixed to the front part of the base plate 47. It is fixed by coming into contact with 53.

That is, when an excessive force is applied to the support frame 45 due to some abnormality, the support frame 45 is displaced against the spring 51, and when this displacement is detected by the limit switch 55, the tire mounting robot 17 is brought to an emergency stop. Ru.

A space is formed in the center of the support frame 45, and sliding tables 57, 59, and 61 are fixed to the front surface of the support frame 45 at the top, bottom, and left so as to surround this space. Upper and lower sliding table 57
, 59 are respectively attached with sliders 63 and 65 so as to be slidable in the vertical direction, while a slider 67 is attached to the left sliding base 61 so as to be slidable in the horizontal direction. These sliders 63, 65° 67 are connected to each slide table 57, 59, 6
Each sliding reciprocating direction is driven by an air cylinder (not shown) built in 1. Each slider 63, 65, 67 has a measurement block 6, respectively.
9, 71.73 are fixed, and a measuring piece 75.77° 79 that comes into contact with the circular outer peripheral surface of the hub H is attached to the tip of each measuring block 69, 71.73 on the central side of the support frame 45. It is being Note that the circular outer peripheral surface of the hub H is
Regardless of its name, it refers to a circumferential surface that is located close to a hub bolt and is concentric with the center of rotation of the wheel. For example, in a vehicle equipped with a drum brake, this corresponds to the outer circumferential surface of a brake drum.

Furthermore, sliders 63 and 65 are provided on the front surface of the support frame 45.
, 67, linear length measuring devices 81, 83, 85 are attached, and these detection rods 87, 89, 91 are attached to brackets 93, which project from the sides of each measuring block 69, 71, 73, respectively. 95 and 97.

Furthermore, a pair of probes 99 for measuring the inclination of the hub H are disposed on the front surface of the support frame 45 so as to protrude forward. As shown in FIG. 5, this measuring stylus 99 is supported in the front-rear direction (left-right direction in FIG. 5) by a bracket 101 fixed to the support frame 45 via a linear bush 103, and is attached forward by a spring 105. Forced.

On the other hand, this bracket 101 has a beam 103 attached to it.
A linear length measuring device 107 is attached adjacent to the linear length measuring device 107, and its detection rod 109 is engaged with a connecting plate 111 fixed to the measuring element 99.

On the other hand, a hub bolt positioning plate 1 is provided at the center of the support frame 45.
13 is in front. As shown in FIG. 2, a pedestal 115 is supported on the rear surface of the support frame 45 so as to be slidable in the front and back direction by a linear guide 117, and an actuator 119 is mounted on the pedestal 115. As shown in the figure, a hub bolt positioning plate 113 is attached to a drive shaft 121 of this actuator 119. Also,
An air cylinder 123 is connected to the pedestal 115,
The pedestal 115 moves in the front-back direction (left-right direction in FIG. 4) by the operation of the air cylinder 123.

The hub bolt positioning plate 113 has a hub bolt B on its front surface.
The actuator 119 rotates the hub bolt positioning plate 113 by a predetermined angle so that the positioning protrusion 125 moves within a predetermined angular range that is larger than the arrangement pitch interval of the hub bolts B. It looks like this.

Next, the function of this measuring/positioning section 35 will be explained. As described above, prior to mounting the tire, the measurement/positioning section 35 is made to face the hub H, and the measurement/positioning section 35 is first directly opposed to the surface of the hub H. That is, when the measurement/positioning section 35 is brought close to the hub H (and the probe 99 first comes into contact with the surface of the hub H, the surface of the hub H is aligned with the direction of travel of the vehicle (assembly line direction). If they are parallel, the pair of probes 99 will be pushed in by the same amount, but if the surface of the hub H is inclined, there will be a difference in the amount of displacement of both probes 99, and the output of the pair of linear length measuring devices 107 will be different. In this case, by rotating the head 33 so that the output of the linear length measuring device 107 is the same, the measurement/positioning section 35 can be brought to face the surface of the hub H.

Next, the center of rotation of the hub H is measured. To do this, first, the upper and lower sliders 63, 65 are brought close to each other, and each measurement piece 75, 77 is brought into contact with the circular outer circumferential surface of the hub H, and the vertical direction is measured from the output of each linear length measuring device 81, 83 at that position. Determine the amount of displacement between the center of the δIll determination and positioning portion 35 and the center of the hub I, and the diameter of the circular outer peripheral surface of the hub H.Next, after retracting the upper and lower sliders G3 and 65,
Move the left slider 67 forward and place the measurement piece 79 on the hub I (
The amount of displacement between the center of the measuring/positioning part 35 in the horizontal direction and the center of the hub H is determined from the output of the linear length measuring device 85 at that position and the previously determined diameter of the hub H. . In this way, the center of rotation of the hub H is measured, and the head 33 is moved based on the measurement result.
Align the centers of the positioning portion 35 and the hub r.

Thereafter, the hub H is rotated to position the hub bolt B at a predetermined rotation angle position.

That is, the air cylinder 123 is operated to advance the hub bolt positioning plate 113, and the positioning protrusion 125 is moved forward.
protrudes to a position where it engages with the hub bolt B, and
The actuator 119 is operated to rotate the hub bolt positioning plate 113. Then, no matter what position the hub bolt B is in, the positioning protrusion 125 comes into contact with the outer peripheral surface of the hub bolt B during the rotation process of the hub bolt positioning plate 113, and as the hub bolt positioning plate 113 further rotates, the positioning protrusion 125 By pressing the hub bolt B, the hub H is rotated, and the hub bolt B is positioned at a predetermined rotation angle position. By locating the hub bolt B in a predetermined position in this way, it becomes possible to subsequently attach the tire using the tire attachment portion 37 and then attach the nut to the hub bolt.

By the way, in the above-mentioned 5-piece measurement/positioning section 35, when measuring the center of the hub H, the measurement pieces 75, 77.79 are brought into contact with the circular outer peripheral surface of the hub H. It is also possible to measure the center of the hub by bringing the measuring pieces 75, 77, 79 into contact with the hub bolt. That is, the four-piece measuring/positioning section 35 of this embodiment is configured so that the measuring pieces 75, 77, and 79 are brought into contact with the outer circumferential surface of the hub bolt. In this case, the four hub bolts are 90°
Since they are arranged at an angular interval of . Therefore, similarly to the case of the circular outer peripheral surface of the hub H, the center of the hub can also be measured using the hub bolt.

<Effects of the Invention> As described above in detail with reference to one embodiment, according to the present invention, the center of the hub can be accurately measured by applying the measurement piece from three sides, top and bottom and from the sides. Based on this, it becomes possible to attach tires to hubs using robots.

Also, there are measurement pieces only on three of the four sides, top, bottom, left and right.
Since the other side is open, a disc brake caliper or the like can be positioned there without interference.

[Brief explanation of the drawing]

FIG. 1 is a front view of a device according to an embodiment of the present invention, and FIG.
The figure is a side view, Figure 3 is a plan view of the same, Figure 4 is the location drawing of Figure 3, Figure 5 is an enlarged cross-sectional view of the contact point, and Figure 6 is the entire automatic tire mounting line. FIG. In the figure, 11 is an automatic tire mounting device, 17 is a tire mounting robot, 19 is a nut feeder, 21 is a nut loader, 23 is a nut robot, 25 is a tire feeding device, 35 is a measurement/positioning section, 37 is a tire mounting section , 75, 77, and 79 are measuring pieces, 81, 83, and 85+ are linear length measuring devices, 113 is a hub bolt positioning plate, 119 is an actuator, and 125 is a positioning protrusion. Patent applicant Mitsubishi Motors Corporation Agent

Claims (2)

[Claims] (1) In an automatic tire mounting device equipped with a robot that positions tires on the hub of a car and tightens nuts,
First and second measuring pieces are attached to the robot so as to be movable in the vertical direction and contact the upper and lower parts of the circular outer peripheral surface of the hub, respectively, so as to be sandwiched between the pieces from above and below; A hub center measuring device comprising: a third measurement piece that is attached and comes into contact with a side of the circular outer circumferential surface of the hub; and a length measuring device that measures the amount of displacement of each of the measurement pieces. (2) In an automatic tire mounting device equipped with a robot that positions a tire on the hub of an automobile having an even number of hub bolts arranged at equal intervals in the circumferential direction and tightens nuts,
first and second measuring pieces, each of which is attached to the robot so as to be movable in the vertical direction and abut on the outer circumferential surface of the hub bolt located at the uppermost and lowermost position, respectively; a third measurement piece that comes into contact with the outer circumferential surface of the hub bolt located most laterally;
A hub center measuring device characterized by comprising a length measuring device for measuring the amount of displacement of each measurement piece.