JPH10338158A - Suspension alignment measuring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To grip a wheel fitting member by an untilting type grip means so that a probe comes in face contact with the reference face of the wheel fitting member without impairing its centering performance and degree of freedom of tilting. SOLUTION: A support frame 8 for supporting a measuring head 10 fitted with a probe 9 tiltably is provided with a pair of grip arms 111 , 112 opened/ closed synchronously. Two rollers 131 , 132 are fitted to one grip arm 111 , and one roller 133 is fitted to the other grip arm 112 . A wheel fitting member is centered and gripped by these three rollers. Each roller is formed of an elastic body and slidably fitted and journalled to a roller shaft 13a parallel with a tangent of a roller contact point of the wheel fitting member.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension alignment measuring apparatus mainly applied to a rear suspension of an automobile, and more particularly to a measuring apparatus used for alignment adjustment in a suspension sub-assembly stage.

[0002]

2. Description of the Related Art Conventionally, as this type of alignment measuring apparatus, Japanese Patent Publication No. 3-61888 discloses a jig means for supporting a suspension sub-assembly in which a suspension is assembled to a sub-frame at a fixed position, and a jig means. Support frame arranged on the lateral side, a measuring element that can abut directly on the reference plane orthogonal to the axle of the wheel mounting member that is supported by the knuckle of the suspension, and the wheel mounting member can be centered and gripped A gripping means, and a measuring head which supports the measuring element so as to be tiltable around the camber axis in the front-rear direction, and is provided with a detecting means for detecting a tilt angle of the measuring element around the camber axis. It is known that a supporting frame is supported by a supporting frame so as to be capable of being pushed inward in a lateral direction via a pressing means so that the supporting frame comes into contact with a reference surface of a wheel mounting member.

In this apparatus, a gripping means is constituted by a plurality of gripping pieces pivotally attached to a measuring element so as to be openable and closable, and the measuring head is pushed inward in the lateral direction to move the measuring element to a reference surface of a wheel mounting member. And the gripping piece is closed to grip the peripheral surface of the wheel mounting member. According to this,
The tracing stylus tilts around the camber axis in accordance with the change of the camber by the alignment adjustment member of the suspension, and the alignment can be adjusted while measuring the camber by the detecting means.

In the above-mentioned publication, the toe is not measured, but the measuring head is supported on the measuring head so as to be tiltable around the vertical toe axis, and the measuring head is mounted on the measuring head. The toe can also be measured by installing a detecting means for detecting the tilt angle around the axis.

[0005]

When the wheel mounting member is gripped by the gripping means, the camber and the toe are not constant before the alignment adjustment, and the axis of the wheel mounting member is set with respect to the gripping center of the gripping means. That is, the wheel mounting member may be gripped while the axle is inclined. When the gripping means is attached to the tracing stylus as in the above-described conventional example, the center line of the tracing stylus becomes the gripping center of the gripping means, and when the wheel mounting member is gripped with the axle inclined with respect to the gripping center, the measurement is performed. The child does not directly contact the reference surface of the wheel mounting member, and the camber and toe cannot be measured accurately.

In view of the above, the present invention provides an alignment measuring apparatus in which a measuring element is reliably brought into direct contact with a reference surface of a wheel mounting member to accurately measure a camber and a toe. That is the task.

[0007]

Means for Solving the Problems In order to solve the above problems,
The present invention is an apparatus for measuring suspension alignment at a suspension sub-assembly stage,
A jig means for supporting the suspension sub-assembly in a fixed position, a support frame arranged laterally of the jig means, and a reference plane perpendicular to the axle of a wheel mounting member which is supported by a knuckle of the suspension. A contact element that can be abutted, a gripping means that can center and hold a wheel mounting member, and a probe that can be tiltably supported around a camber axis in the front-rear direction and around a toe axis in a vertical direction. A camber detecting means for detecting a tilt angle around the camber axis, and a measuring head having a toe detecting means for detecting a tilt angle of the measuring element around the toe axis are provided. A supporting frame is supported by a supporting frame so as to be capable of being pushed inward in a lateral direction via a pressing means so as to be in contact with a reference surface. In the supporting frame, a plurality of gripping arms constituting gripping means are mounted on a wheel mounting member. Each gripping arm supports an elastic roller made of an elastic body that comes into contact with the peripheral surface of the wheel mounting member. It is rotatably supported.

According to the present invention, the tilting of the measuring element is not restricted by the gripping means, and the measuring element is pushed straight inward in the horizontal direction, so that the measuring element can be surely straightened to the reference surface of the wheel mounting member. Abut. Therefore, the camber and the toe can be accurately measured by each detecting means.

On the other hand, according to the present invention, since the gripping means does not tilt around the camber axis or the toe axis, tilting in the camber direction or the toe direction due to the alignment adjustment of the wheel mounting member may be restricted. However, in the present invention, since each gripping arm serving as gripping means abuts on the peripheral surface of the wheel mounting member via the elastic roller, the elastic deformation and rotation of the elastic roller allow the wheel mounting member to tilt, which hinders alignment adjustment. Does not occur. In this case, if the elastic roller is slidably supported on the gripping arm in the axial direction of the roller shaft, the degree of freedom of the wheel mounting member is further increased.

By the way, in order to center the wheel mounting member, it is necessary to hold at least three peripheral parts. In this case, three gripping arms may be provided, but this complicates the structure. On the other hand, a pair of upper and lower gripping arms are provided, and one elastic arm supports two elastic rollers that abut against the peripheral surface of the wheel mounting member on both sides in the circumferential direction of the vertical diameter line of the wheel mounting member, If one elastic roller that contacts the peripheral surface of the wheel mounting member on the diameter line is supported by the other gripping arm, the wheel mounting member can be gripped by the two gripping arms without deteriorating the centering ability. In this case, a synchronization mechanism that opens and closes both grip arms in synchronization is required.This synchronization mechanism includes a rack extending downward connected to the upper grip arm, and a rack extending upward connected to the lower grip arm. And a pinion that meshes with both racks and is supported by the support frame.

Further, if the support frame can be driven up and down and a displacement detecting means for detecting the displacement of the support frame in the up and down direction is provided, the change in camber and toe due to the up and down movement of the suspension can be measured. If a means for pressing the support frame in the front-rear direction is provided, the change in camber and toe when a force in the front-rear direction such as during braking is applied can be measured.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to an alignment measuring device for a multilink type suspension shown in FIG. 9 used as a rear suspension of an automobile will be described.

The multi-link type suspension is a suspension in which a lower arm connected to the lower part of the knuckle A and an upper arm connected to the upper part are each composed of a plurality of links. In the multi-link type suspension shown in FIG. It consists of a trailing link B extending diagonally forward connected to the front end, a lower link C extending laterally connected to the lower middle of the knuckle A, and a control link D extending laterally connected to the lower rear end of the knuckle A. And
The upper arm is composed of a laterally extending upper link E connected to the upper portion of the knuckle A, and a diagonally rearwardly extending leading link F connected to the upper portion of the knuckle A. These links are connected to the subframe G. The suspension sub-assembly is assembled. The connecting position of the control link D to the sub-frame G can be adjusted in the lateral direction by an alignment adjusting member Da composed of an eccentric cam, and the connecting of the control link D is performed so that the toe and camber measured by the alignment measuring device become predetermined values. Adjust the position. In the figure, H is a wheel mounting member composed of a brake disk that is supported by a knuckle A.

As shown in FIG. 1, the alignment measuring apparatus includes jig means 2 arranged on a bed 1 and measuring means 3 and 3 arranged on both sides of the jig means 2.

The jig means 2 supports the suspension sub-assembly in a fixed position, and fixes the suspension sub-assembly carried in by a conveyor (not shown) arranged so as to intersect the bed 1 on both right and left sides of the sub-frame G. It comprises a pair of left and right work receivers 4 and 4 that can be moved up and down and supported by a unit, and a pair of undulating clamp arms 5 and 5 that are provided in front and rear pairs respectively corresponding to the work receivers 4. Each work receiver 4 is raised and lowered by a cylinder 4a, and the clamp arm 5 is raised and lowered by a cylinder 5a. Then, when the suspension sub-assembly is carried in, first, the clamp arm 5 is erected, then the work receiver 4 is raised to lift the sub-frame G, and the sub-frame G is sandwiched between the sub-frame G and the clamp arm 5. Support in place.

The measuring means 3 is, as shown in FIGS.
A column 6 which is moved back and forth by a cylinder 6a along a rail 6b on the bed 1 to a laterally outward retreat position and a laterally inward measuring position, and a column 6 which is constituted by two cylinders 7a and 7b.
Lifting frame 7 which is raised and lowered along a rail 7c fixed to
And a support frame 8 which is pushed forward and backward along a rail 8c fixed to the lifting frame 7 by the pair of cylinders 8a and 8b. The support frame 8 has a lateral side plate portion 8d and a forward side plate portion 8f coupled to the side plate portion 8d via a beam 8e, and a reference surface Ha orthogonal to the axle of the wheel mounting member H.
Measuring head 1 supporting cup-shaped measuring element 9 facing
And a pair of upper and lower gripping arms 11 serving as gripping means for gripping the wheel mounting member H from above and below while supporting the wheel mounting member H from above and below in a laterally movable manner on a guide block 8g mounted on the side plate portion 8d.
_1, 11 ₂ are openably supported in a vertical direction to the side plate portion 8f.

The two cylinders 7a, 7 for the lifting frame 7
b is mounted on a common connecting plate 7d with one side facing downward and the other facing upward, and a piston rod extending downward from a downward cylinder 7a is attached to a column 6 to a reaction force receiver 6c which can be vertically adjusted in position. A piston rod extending upward from the upward cylinder 7b is connected to an arm 7e fixed to an elevating frame 7 protruding through a vertically long hole 6d formed in the column 6, and the cylinder 7a is contracted from a neutral position shown in the figure. The lifting frame 7 is lowered by the operation, and the lifting frame 7 is raised by the extension operation of the cylinder 7b. According to the lifting and lowering of the lifting frame 7, the wheel mounting member H is moved up and down via the support frame 8 and the gripping arms 11 ₁ and 11 ₂ to simulate the upward bump operation and the downward rebound operation of the suspension with respect to the vehicle body. Is

A reflecting plate 12a is attached to the arm 7e, and an oscillating or optical distance sensor 12 for measuring a distance between the supporting plate 6 and the reflecting plate 12a is attached thereto. 7, ie, a displacement detecting means for detecting the vertical displacement of the support frame 8.

The pair of cylinders 8a, 8 for the support frame 8
b is attached to the upper end of the support frame 8 with one facing forward and the other facing backward, and each of the reaction force receivers 7f in which the piston rods of the cylinders 8a and 8b are attached to the upper end of the lifting frame 7 in a front-rear pair. , The support frame 8 is pressed rearward by the extension operation of the forward cylinder 8a, and the support frame 8 is pressed forward by the extension operation of the rearward cylinder 8b. It is possible to simulate the condition that acts on.

As shown in FIGS. 6 and 7, the measuring head 10 includes a head frame 10a and a first yoke 1 rotatable around a vertical toe shaft 10b supported by the head frame 10a.
0c and a second joint 10e rotatably around a camber shaft 10d in the front-rear direction supported by the first yoke 10c. Then, the second yoke 1
0e, attach the tracing stylus 9 to the toe shaft 10
It is supported so as to be tiltable around b and around the camber shaft 10d. The head frame 10a is provided with a toe detecting means 10f composed of a rotary encoder connected to the lower end of the toe shaft 10b, and the first yoke 10c is provided with a camber detecting means 10g composed of a rotary encoder connected to the front end of the camber shaft 10d. And the detecting means 10f and 10g detect the tilt angles of the tracing stylus 9 around the toe axis 10b and the camber axis 10d. A pair of cylinders 10h, 10h facing the side plate of the tracing stylus 9 is further attached to the head frame 10a, and the tracing stylus 9 is held in a neutral position in which the tracing stylus 9 faces directly beside by the extension operation of both cylinders 10h, 10h. I can do it.

The measuring head 10 is supported by a guide block 8g via a pair of guide bars 10i, 10i extending laterally outward from the head frame 10a so as to be slidable in the horizontal direction, and attached to the guide block 8g. The measuring head 10 is pushed inward in the horizontal direction by the cylinder 10j serving as a pressing means so that the measuring element 9 can abut on the reference surface Ha of the wheel mounting member H.

Each of the gripping arms 11 ₁ and 11 ₂ has a first movable frame 11b supported by a rail 11a fixed to the side plate portion 8f so as to be vertically movable, and a first movable frame 1 by a cylinder 11c.
It is composed of a second movable frame 11e which advances and retreats in the horizontal direction along a rail 11d fixed to 1b, and an arm body 11f attached to the second movable frame 11e. Upper grip arm 11
The first movable frame 11b _1, and the projection 11g is provided to protrude to the reverse side of the side plate portion 8f through vertical elongated hole 8h formed in the side plate portion 8f, downwardly on the rear surface upper portion of the side plate portion 8f The piston rod of the attached cylinder 11h is connected to the projection 11g. Furthermore, both the gripping arms 11 ₁ of upper and lower, 11 ₂ of the first movable frame 11b, the rack 11b extending people lower and upper husband to 11i, 11i are attached, both racks 11i on the side plate portion 8f, 11i And a pinion 11j that meshes with the shaft. Thus, the two gripping arms 11 ₁ and 11 ₂ are opened and closed in the vertical direction in synchronization with each other by the operation of the cylinder 11 h with the arrangement height of the pinion 11 j as the opening / closing center. In FIG. 2, 11k is each rack 11i.
Backup roller.

[0023] The upper gripping arm 11 ₁ of the arm body 11f
Are provided with _two elastic rollers 13 ₁ and 13 ₂ that abut against the peripheral surface of the wheel mounting member H on both sides in the circumferential direction of the vertical diameter line of the wheel mounting member H.
The _second arm main body 11f, the elastic roller 13 ₃ abuts with said diameter line on the peripheral surface of the wheel mounting member H is provided. Each of these elastic rollers 13 ₁ , 13 ₂ , 13 ₃
It is slidably fitted and supported on each roller shaft 13a attached to each arm body 11f and parallel to the tangent line of each roller contact point of the wheel mounting member H. And each elastic roller 13
_1, 13 _2, 13 ₃ the axially opposite sides of the spring 13b, are elastically held at the central portion in the axial direction of the roller shaft 13a at 13b. The elastic rollers 13 ₁ , 13 ₂ , and 13 ₃ are formed of an elastic body such as urethane rubber.

At the time of alignment adjustment, the suspension sub-assembly is supported at the fixed position by the jig means 2 as described above, and then the column 6 of each measuring means 3 is advanced to the measuring position, and the lifting frame 7 is set at the neutral position. The upper and lower gripping arms 11 ₁ and 11 ₂ are closed and the peripheral surface of the wheel mounting member H is
The wheel mounting member H is gripped by the elastic rollers 13 ₁ , 13 ₂ and 13 ₃ , and the wheel mounting member H is centered so as to face the measuring element 9.
Here, the neutral position of the lifting frame 7 is set to a height such that the wheel mounting member H is held at the neutral position in the vertical direction (a position corresponding to 1 G).

Next, the second movable frame 11e of each of the gripping arms 11 ₁ and 11 ₂ is pressed inward in the horizontal direction by the cylinder 11c with a pressing force of about 2 kg to 3 kg. According to this, the wheel mounting member H is pushed inward in the lateral direction via the elastic rollers 13 ₁ , 13 ₂ , 13 _3, and the links B, C,
Knuckle A side connection part of D, E, F and subframe G
The play of the side connection is eliminated.

Next, the measuring head 10 is pushed inward in the lateral direction by the cylinder 10j to bring the measuring element 9 into contact with the reference surface Ha of the wheel mounting member H. At this time, the stylus 9 is initially held in the neutral position by the cylinder 10h, and after the abutment on the reference surface Ha of the wheel mounting member H, the tilting regulation of the stylus 9 by the cylinder 10h is released. According to this, the tracing stylus 9 tilts following the reference plane Ha and comes into direct contact with the reference plane Ha.

Next, the toe detected by the toe detecting means 10f and the camber detected by the camber detecting means 10g are respectively predetermined by an alignment adjusting member Da for adjusting the connection position of the control link D of the suspension to the subframe G. Adjust the alignment so that the target value is obtained.

When the wheel mounting member H is at the neutral position in the vertical direction, the target values of the toe and the camber are each zero, and if the alignment adjusting member Da is loosened, the measuring element 9 is moved to the neutral position by the cylinder 10h. When the wheel mounting member H is brought into contact with the reference surface Ha of the wheel mounting member H while being restrained, the toe and the camber are corrected so that each of the toe and the camber becomes zero. The alignment adjustment can also be performed by tightening the alignment adjustment member Da.

Next, the lifting frame 7 is moved up and down from the neutral position by the cylinders 7a and 7b, and the data from the distance sensor 12 and the data from the toe and camber detecting means 10f and 10g are sampled. The change of the toe and the camber due to the directional displacement is measured, and the change of the toe and the camber when the support frame 8 is pressed in the front-rear direction by the cylinders 8a and 8b and the force in the front-rear direction is applied is measured.

Here, when the wheel mounting member H is tilted in the toe direction, the wheel mounting member H is
1 _1, 11 ₂ to but displaced in longitudinal direction while rotating the vertical line around the upper gripper arm 11 in the vertical line around the rotation
₁ of the elastic roller 13 _1, 13 ₂ is rotated, the elastic roller 13 ₁ of the upper gripper arm 11 ₁ with a lower gripper arm 11 ₂ of the elastic roller 13 ₃ in the front-back direction displacement slides along its roller shaft 13a , 13 ₂ are elastically deformed while sliding along the roller shaft 13a of each and thus, the wheel mounting member H
In the toe direction is allowed.

Further, when the tilting of the camber direction of the wheel mounting member H, although the wheel mounting member H is displaced in the vertical direction together with the rotation in a horizontal line around the longitudinal direction with respect to the gripping arm 11 _1, 11 _2, horizontal lines around , The elastic rollers 13 ₁ , 13 ₂ , and 13 ₃ rotate, and the elastic roller 13 ₃ of the lower grip arm 11 ₂ is elastically deformed by the vertical displacement, and the elastic rollers 13 ₁ , 13 of the upper grip arm 11 _1
2 are elastically deformed while sliding along the respective roller shafts 13a, thus allowing the wheel mounting member H to tilt in the camber direction.

As described above, since the wheel mounting member H is held by the three elastic rollers 13 ₁ , 13 ₂ , and 13 ₃ with a degree of freedom of tilting in the toe and camber directions, alignment adjustment and alignment can be performed. The dynamic change can be measured without any trouble.

However, the holding arm 1 by the cylinder 11h
1 _1, 11 ₂ of the closing force, i.e., when strong clamping force on the wheel mounting member H, impaired flexibility of the tilting of the wheel mounting member H, connecting part and sub-frame G of the knuckle A side of each link of the suspension The elastic deformation of the rubber bush provided on the side connecting portion becomes larger than when mounted on the vehicle body, so that the alignment cannot be measured correctly. FIG. 8 shows the change of the toe due to the vertical displacement of the wheel mounting member H,
It is a graph showing the positive side of the vertical displacement as the rebound side, the negative side as the bump side, the positive side of the toe as the toe-in side, and the negative side as the toe-out side. In the figure, the line a is the reference change characteristic of the toe obtained from the design value of the suspension, the line b is the toe change characteristic measured when the clamping force is set to 62 kgf,
The c-line is a toe change characteristic measured when the clamping force is set to 124 kgf. When the clamping force is set to 62 kgf, the characteristic matches the reference characteristic with considerable accuracy. However, when the clamping force is set to 124 kgf, the characteristic changes from the reference characteristic. It will shift considerably. Also, if the clamping force is small, the centering of the wheel mounting member H will be poor. Therefore, the clamping force is 50kgf ~
It should be set in the range of 70 kgf.

Although the center of tilt of the wheel mounting member H does not coincide with the center of tilt of the tracing stylus 9, the tracing stylus 9 is perpendicular to the reference surface Ha of the wheel mounting member H with the tilting of the wheel mounting member H. Slides against the reference plane Ha while contacting the
This sliding absorbs the mismatch between the two tilting centers. Therefore, the tracing stylus 9 tilts at the same angle as the wheel mounting member H,
The toe and camber detecting means 10f and 10g for detecting the tilt angle of the tracing stylus 9 can accurately detect the toe and camber. However, the stylus 9 using the cylinder 10j
When the pressing force becomes excessive, the reference surface H of the wheel mounting member H
a slidability of the tracing stylus 9 with respect to the
When the pressing force of the probe becomes too small, the stylus 9
The pressing force of the stylus 9 is 9.0 kg.
It should be set in the range of f to 10.0 kgf.

If the tracing stylus 9 interferes with the wheel mounting hub bolt Hb implanted on the reference surface Ha due to its sliding, the toe and camber cannot be measured accurately. Here, the wheel mounting member H at the neutral position of the lifting frame 7
If the amount of misalignment of the wheel mounting member H with respect to the tracing stylus 9 is equal to or less than a predetermined allowable value, the hub bolt Hb is within the tilting range of the wheel mounting member H in the toe direction and the camber direction due to the vertical movement of the wheel mounting member H due to the elevation of the lifting frame 7. The stylus 9 does not interfere. In this case, the elastic rollers 13 ₁ , 1
3 _2, 13 longitudinal elastic coefficient of the elastic _{body 3} constituting the 1.5 kg /
If it is smaller than mm ^2, the centering accuracy of the wheel mounting member H deteriorates, and the amount of misalignment of the wheel mounting member H with respect to the tracing stylus 9 at the neutral position of the lifting frame 7 may exceed an allowable value. The elastic body has a longitudinal modulus of 2.3 kg.
If it is larger than / mm ^{2, the} degree of freedom of tilting of the wheel mounting member H is impaired, and the elastic deformation of the rubber bush provided at the connecting portion of each arm of the suspension becomes larger than when mounted on an actual vehicle, so that the alignment is correctly measured. become unable. Thus, the elastic rollers 13 _1, 13 _2, 13 _3, modulus of longitudinal elasticity should form an elastic body in the range of ^{1.5kg / mm 2 ~2.3kg / mm 2} .

[0036]

As is apparent from the above description, according to the present invention, the tilting of the tracing stylus is not restricted by the gripping means, and the tracing stylus is surely and directly on the reference surface of the wheel mounting member. In addition to being able to abut, the wheel mounting member can be gripped by the gripping means without impairing the degree of freedom of tilting, and the toe and camber can be accurately measured.

[Brief description of the drawings]

FIG. 1 is a perspective view of an example of the apparatus of the present invention.

FIG. 2 is a front view of a measuring means of the apparatus of FIG.

FIG. 3 is a left side view of FIG. 2;

FIG. 4 is a right side view of FIG. 2;

FIG. 5 is a plan view of FIG. 2;

FIG. 6 is an enlarged sectional view of the measuring head taken along the line VI-VI in FIG. 2;

FIG. 7 is a sectional view taken along line VII-VII of FIG. 6;

FIG. 8 is a graph showing a change in toe change characteristics due to a clamping force.

FIG. 9 is a perspective view of a suspension.

[Explanation of symbols]

H Wheel mounting member Ha Reference surface 2 Jig means 7 Elevating frame 8 Support frame 9 Measuring element 10 Measuring head 10b Toe shaft 10d Camber shaft 10f Toe detecting means 10g Camber detecting means 10j Cylinder (pressing means) 11 ₁ , 11 ₂ Gripping arm 11i rack 11j pinion 12 a distance sensor (displacement detector) 13 _1, 13 _2, 13 ₃ elastic roller 13a roller shaft

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI G01M 17/007 G01M 17/00 R

Claims (6)

[Claims] 1. An apparatus for measuring alignment of a suspension at a sub-assembly stage of a suspension, comprising: jig means for supporting a suspension sub-assembly in a fixed position; a support frame disposed laterally to the jig means; A tracing stylus that can abut the reference plane perpendicular to the axle of the wheel mounting member that is supported by the knuckle of the suspension, a gripper that can center and hold the wheel mounting member, Camber detecting means for tiltably supporting the probe around the camber axis and detecting the tilt angle of the probe around the camber axis, and toe detection for detecting the tilt angle of the probe around the toe axis And a measuring head to which the measuring head is attached. The measuring head is slid on the supporting frame via the pressing means so that the measuring element contacts the reference surface of the wheel mounting member. A plurality of gripping arms constituting gripping means are supported on a support frame so as to be freely openable and closable in a radial direction of the wheel mounting member; A suspension alignment measuring device, wherein an elastic roller made of an elastic body contacting a surface is rotatably supported around a roller axis parallel to a tangential direction of each roller contact point of the wheel mounting member. 2. The suspension alignment measuring device according to claim 1, wherein the elastic roller is supported on the grip arm so as to be slidable in the axial direction of the roller shaft. 3. A pair of upper and lower gripping arms are provided as the gripping arms, and two elastic rollers contact one of the gripping arms with the circumferential surface of the wheel mounting member on both circumferential sides of a vertical diameter line of the wheel mounting member. 3. The suspension alignment measuring device according to claim 1, wherein one elastic roller that contacts the peripheral surface of the wheel mounting member on the diameter line is supported by the other gripping arm. 4. . 4. A rack extending downwardly connected to the upper gripping arm, a rack extending upwardly connected to the lower gripping arm, and a pinion that meshes with both racks and is supported by the support frame. 4. The suspension alignment measuring device according to claim 3, wherein the rack and the pinion constitute a synchronization mechanism that opens and closes both gripping arms in synchronization. 5. The apparatus according to claim 1, wherein said support frame is vertically drivable and a displacement detecting means for detecting a vertical displacement of said support frame is provided.
Item 6. The suspension alignment measuring device according to Item 1. 6. The suspension alignment measuring device according to claim 1, further comprising means for pressing the support frame in the front-rear direction.