JP2002131005A - Spindle supporting structure of measuring instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spindle supporting structure of measuring instrument capable of improving resistances to vibration and impact and also capable of improving durability and accuracy. SOLUTION: In the supporting structure having a scale 10 and a detector 15, the scale 10 is mounted at a scale holder 9, the holder 9 and a spindle 7 are supported by bearings which are mounted at predetermined spaces in the respective axial directions, a bearing mechanism 20 to support the holder 9 is composed of two pairs whose perimeters are touched respectively to both side surfaces of the holder 9, and each of the mechanism 20 is composed of a first and second bearing 17, 18 crossing at roughly right angles. Therefore, the solidity at causing vibration and impact is improved, the resistances to vibration and impact are improved and the durability is allowed to increase.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spindle of a measuring instrument for measuring a dimension of an object to be measured from an axial displacement of the spindle by supporting a spindle in a measuring instrument body in the axial direction. Regarding the structure. For example, it can be used for a spindle support structure of a linear displacement measuring device such as a dial gauge or a linear gauge.

[0002]

2. Description of the Related Art In a measuring instrument such as a dial gauge or a linear gauge, a spindle is supported on a main body frame so as to be movable in the axial direction, and a displacement amount of the spindle in an axial direction is measured by a mechanical type, an optical type, a capacitance type, or the like. Detected by the detecting means, the dimensions and the like of the object to be measured are measured from the displacement amount. Among them, a linear gage (LG) having a large measuring range (about 100 mm or more) has been demanded.
In this case, the problem is what to do with the scale supporting structure to which the spindle is attached. Conventionally, as the scale support structure, there are known (1) a structure in which the scale is fixed to the gauge body side and the detector is moved, and (2) a structure in which the scale is moved.

[0003]

However, the conventional spindle support structure has the following problems. In other words, in the case of the structure of (1), there is a problem in routing and durability, such as the cable coming out of the detector being stretched or contracted and entangled with the movement of the detector, making it impossible to move smoothly, and the like. In recent LGs that require high reliability and high durability, it is difficult to employ a detector moving type support structure. In the case of structure (2), the spindle below the scale is supported by a stroke bearing or linear bush, so when a long scale is used, the rigidity between the scale and the light-receiving element at the detector position is weak. Poor impact resistance. Further, it is difficult to match the scale scale surface with the spindle axis, and an error occurs due to Abbe offset. Furthermore, a guide pin for stopping the rotation of the spindle is required on the spindle side, and a groove for the guide pin to slide on the main body side is required.

[0004] An object of the present invention is to solve such a conventional problem. A measuring instrument capable of improving vibration resistance and shock resistance as well as durability and accuracy. A spindle support structure.

[0005]

According to the present invention, there is provided a spindle support structure for a measuring instrument, wherein the scale has a scale surface indicating displacement and is connected to the spindle; and a scale fixed to the measuring instrument main body. A spindle support structure of a measuring device for measuring a dimension or the like of an object to be measured from an axial displacement amount of the spindle, wherein the scale extends in an axial direction of the spindle. The scale holder and the spindle are mounted on a holder, and the scale holder and the spindle are supported by bearings provided at predetermined intervals in respective axial directions. Bearings supporting the scale holder are guided on both side surfaces of the scale holder. The bearing is composed of two sets of bearing mechanisms, each of which has an outer periphery in contact with each other. First differentially, and it is characterized in that it is constituted by a second bearing.

According to the present invention, since the scale holder is supported by two sets of bearings including first and second bearings whose both side surfaces substantially intersect with each other, both directions intersecting the longitudinal direction of the scale holder. , And the movement in the direction of forming an inner angle across the center line of the guided portion is restricted. Therefore, the rigidity when vibration and impact are applied is improved, and the vibration resistance and shock resistance can be improved, and the durability can be improved.

[0007] Two sets of bearings comprising first and second bearings are arranged along guided portions on both sides of the scale holder, and guide the scale holder, in other words, the spindle, in the axial direction of the guided portions. For this reason, the detent pin of the spindle and the guide groove of the pin are not required, and there are no sliding parts due to the reciprocating motion of the spindle. The troubles such as have disappeared.

In the present invention, the intersection angle between the first and second bearings is preferably substantially 90 °, but may be, for example, 60 ° or less, such as 90 ° or less. Depending on the shape of the guided portion, it may be close to 180 °. In short, any angle may be used as long as the movement of the guided portion in the line direction connecting the guided portions on both side surfaces of the scale holder and the crossing direction forming an inner angle across the line can be restricted.

According to a second aspect of the present invention, there is provided a spindle supporting structure for a measuring instrument according to the first aspect, wherein the scale surface of the scale and the axis of the spindle are located on the same plane. It is characterized by having.

In the present invention, since the scale surface of the scale and the axis of the spindle are located on the same plane,
Abbe error can be eliminated, and accuracy can be improved.

A spindle support structure for a measuring instrument according to claim 3 is the spindle supporting structure for a measuring instrument according to claim 1 or 2, wherein the first and second bearings of each set are Each of the opposing surfaces is supported by a bearing holder attached to the measuring instrument main body. According to this aspect of the invention, since the orthogonal mounting shaft can be extended from the bearing holder, the first and second bearings can be supported by one bearing holder, and the number of members used can be reduced.

According to a fourth aspect of the present invention, in the spindle support structure of the measuring instrument main body according to any one of the first to third aspects, the bearings supporting the spindle are arranged in parallel with each other. And a first and a second linear bush that are provided and house the spindle therein. In the present invention, since the spindle can be supported by the two linear bushes, the spindle can be stably supported, and highly accurate measurement can be performed.

According to a fifth aspect of the present invention, there is provided a spindle supporting structure for a measuring instrument according to any one of the first to fourth aspects, wherein the scale holder is driven in the forward and reverse directions by motor driving. A belt drive is rotatably connected to the spindle drive, and the spindle is displaced in the axial direction as the belt drive rotates. In the present invention, since the scale holder can be displaced by driving the motor, automation can be achieved.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a linear gauge (LG) 1 as a linear displacement measuring device of the present embodiment includes a measuring device main body 2, and the measuring device main body 2 is covered with a vertically long main body frame 3 and the main body frame 3. Body cover 4
And is configured. The main body frame 3 is provided with a tubular stem 5 extending through the bottom wall along the longitudinal direction of the main body frame 3.

In the main body frame 3, a cable extraction hole 3A having an L-shaped cross section for extracting a cable from the detector 15 is provided.
Further, a cable connection port 12 is provided on the outer periphery of the main body frame 3, and a protection cable 13 for protecting the cable taken out from the cable extraction hole 3A is attached to the cable connection port 12. ing.

A spindle 7 is provided inside the stem 5 so as to be movable in its axial direction (vertical direction in FIG. 1) supported by two linear bushes 6 and 6 arranged in parallel.
A tracing stylus 7A is provided at the tip (lower end in FIG. 1) of the spindle 7, and the rear end (upper end in FIG. 1) of the spindle 7 is fitted into the guide cylinder 8. Such a spindle 7 is, for example, movable about 100 mm. That is, measurement within that range is possible.

A scale holder 9 is attached to the rear end of the spindle 7 by bonding or the like. At this time, a part of the rear end of the guide cylinder 8 and the spindle 7 is cut out, and the front surface in the thickness direction (the detector 15 side described later) is brought into contact with the cutout part at the lower part of the scale holder 9; It is fixed by bonding or the like.

The scale holder 9 is formed in a substantially rectangular parallelepiped shape and extends in the axial direction of the spindle 7. The scale holder 9 has a front surface in the thickness direction (a detector 15 side described later) on the surface thereof. Scale 1 with scale displayed
0 is fixed by bonding or the like. A guide shaft 11 which is a guided portion having substantially the same length as the scale holder 9 is fixed to both sides of the scale holder 9 in the width direction by bonding or the like. Therefore, the spindle 7,
The scale holder 9, the scale 10, and the guide shaft 11 are an integral structure. These lower parts are inserted into the through holes 3B and the stem 5 formed in the bottom wall of the main body frame 3. The scale holder 9 is formed to have a length such that the spindle holder 7 can measure up to, for example, about 100 mm.

Here, as shown in FIG. 1, each member is arranged so that the axis 7B of the spindle 7 and the surface of the scale 10, that is, the scale surface 10A are located on the same plane.
The Abbe offset between the scale surface of the scale 10 and the axis of the spindle 7 is zero.

On the other hand, on the upper part of the main body frame 3, the movement of the scale holder 9, that is, the movement (displacement) of the spindle 7 is detected from the scale of the scale 10, and the amount of displacement is detected as an electric signal. Detector 1 to detect
5 are provided.

As shown in FIG. 2, the main body frame 3 is provided with two sets of bearing mechanisms 20.
That is, each bearing mechanism 20 is composed of two bearings 17 and 18 crossing each other and a bearing holder 19 that supports these bearings 17 and 18 from sides facing each other. Fifteen
Is provided at a position substantially opposed to. The two bearings 17 and 18 are supported by shafts provided on the bearing holder 19 so as to protrude from surfaces orthogonal to each other.
In the present embodiment, the two bearings 17, 18 are
They intersect at an angle of approximately 90 °.

The two bearings 17 and 18 are arranged slightly offset in the axial direction of the spindle 7 with respect to the scale holder 9. Further, the side surface on the side where the bearings 17 and 18 intersect and the guide shafts 11 on both sides of the scale holder 9 are in contact with each other, so that the guide shaft 11 can be guided along the bearings 17 and 18. I have. In other words, a direction perpendicular to the longitudinal direction of the scale holder 9 and the center line of the guided portion are interposed at 90 degrees.
While the movement in the ° direction is regulated, the scale holder 9
Both sides are supported by two bearings 17 and 18, respectively, and are guided in the axial direction of the spindle 7.

A substantially crank-shaped bracket 26 is attached to the back of the scale 10 by bolts or the like, and a belt drive 27 is integrally attached to the bracket 26. The belt drive 27 is bridged between mounting shafts 28 and 29 provided on the spindle 7 side of the main body frame 3 and on the opposite side. The first bevel gear 30 is provided on the mounting shaft 29.

The mounting shaft 2 of such a belt drive 27
A motor 31 is provided on the extension line on the 9th side via a support base 3, and the main shaft of the motor 31 is provided with the first bevel gear 3.
The second shaft bevel gear 32 is provided so as to be able to mesh with zero. Accordingly, by driving the motor 31, the second shaft bevel gear 32 and the first bevel gear 30 rotate, and the first bevel gear 30
With this rotation, the belt drive 27 rotates, and accordingly, the scale holder 9 moves up and down in the figure, and the spindle 7 moves up and down in the figure.

The motor 31 is rotatable in the forward and reverse directions, whereby the scale holder 9 can be moved in the axial direction of the spindle 7 so as to be able to move forward and backward. In this embodiment, when the motor 31 is rotated in the normal rotation direction, the spindle 7 advances from the stem 5, and when the motor 31 is rotated in the reverse direction, the spindle 7 is retracted toward the stem 5. I have.

Next, a case where the measuring device having such a configuration is used to measure, for example, the thickness dimension of an object to be measured will be described. First, after fixing the main body frame 3 to a stand having a surface plate or the like, the motor 31 is rotated in the reverse direction, the belt drive 27 is rotated in the reverse direction, and the scale holder 9 and the spindle 7 are moved by predetermined dimensions in the figure. It is moved upward, and the object to be measured is placed on the surface plate just below it.

Next, by rotating the motor 31 in the normal rotation direction, the spindle 7 is displaced downward, and the tracing stylus 7A of the spindle 7 is brought into contact with the object to be measured. At this time, the spindle 7 is moved downward in the axial direction while the scale holder 9 is supported by the two bearings 17 and 18 by the two rows of linear bushes 6 and 6 in the lower part of the figure. By reading the detection of the amount of movement of the scale 10 by the detector 15 when the spindle 7 comes into contact with the object to be measured, the thickness of the object to be measured can be measured.

According to the above embodiment, the following effects can be obtained. (1) Since both sides of the scale holder 9 are supported by the first and second bearings 17 and 18 constituting the bearing mechanism 20, the rigidity when vibration and impact are applied can be improved. Therefore, the vibration resistance and the shock resistance can be improved, and the durability can be improved.

(2) Since the scale holder 9 is supported by the first and second bearings 17 and 18 as described above, there is no need for the detent pin of the spindle and the guide groove of the pin as in the related art. became. For this reason, there are no sliding points due to the reciprocating motion of the spindle, and problems such as an increase in the number of members, troubles such as groove processing, and impairing smooth displacement are eliminated.

(3) Since the scale surface of the scale 10 and the axis of the spindle 7 are located on the same plane, and the Abbe offset amount is zero, it is possible to eliminate Abbe error and to improve accuracy. Can be improved.

(4) Since the two sets of bearing mechanisms 20 supporting the scale holder 9 are provided at positions facing the detector 15, the gap (interval) between the detector 15 and the scale 10 is appropriately maintained. It is possible to perform high-precision measurement, and even if the position of the detector 15 is set at a position where the spindle 7 can move, for example, about 100 mm, the scale at the position of the detector 15 can be obtained. Since the holder 9 can be supported, a large measurement range can be secured.

(5) The bearing holders 19 for supporting the bearings 17 and 18 are provided from the inside facing each other.
8 can be supported, so that the first and second bearings 17, 18 can be supported by one bearing holder, thereby reducing the number of members used.

(6) The spindle 7 is supported by the two linear bushes 6, 6 arranged side by side, and is provided so as to be movable in the axial direction, so that the spindle 7 can be stably supported. , High-precision measurement can be ensured.

(7) A belt drive 27 is connected to the scale holder 9 so as to be rotatable in the forward and reverse directions by the driving of a motor 31. As the belt drive 27 rotates, the scale holder 9 and the spindle 7 are rotated. It can be moved and displaced in the direction, and automation can be achieved.

The present invention is not limited to the above-described embodiment, but may be modified as follows as long as the object of the present invention can be achieved.
For example, in the above embodiment, two bearings 17, 1
8 intersect with each other at an angle of about 90 degrees, but is not limited thereto, and may be, for example, 60 degrees or less, or 90 degrees or less, or may be close to 180 degrees. In short, any angle may be used as long as it can restrict the movement of the guide shaft 11 in the direction of the line connecting the guide shafts 11 on both sides of the scale holder 9 and in the cross direction forming an inner angle across the line.

In the above embodiment, the two bearings 17 and 18 cross each other at an angle of about 90 degrees and are slightly displaced from the scale holder 9 in the axial direction of the spindle 7. However, the axial displacement of the spindle 7 with respect to the scale holder 9 may not be required, and may be provided at the same level.

In the above-described embodiment, the belt drive 27 is rotated by driving the motor 31, and the scale holder 9 and the spindle 7 can be moved and displaced in the axial direction as the belt drive 27 rotates. However, the present invention is not limited to this, and the motor 7 and the belt drive 27 are not provided.
May be adopted.

[0038]

According to the spindle support structure of the measuring instrument of the present invention, the scale holder is supported by the two sets of first and second bearings whose both sides substantially intersect with each other. The movement in both directions intersecting the longitudinal direction of the holder and in the direction forming an inner angle across the center line of the guided portion is restricted. Therefore, the rigidity when vibration and impact are applied is improved, and the vibration resistance and shock resistance can be improved, and the durability can be improved. Further, because of the above-described structure, the conventional detent pin for the spindle and the guide groove of the pin are not required, and the sliding portion is eliminated due to the reciprocating motion of the spindle. As a result, the number of members increases due to them,
Troubles such as trouble in groove processing and loss of smooth displacement have been eliminated.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing a main part of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Measuring instrument (linear gauge) 2 Measuring instrument main body 6 Linear bush 7 Spindle 9 Scale holder 10 Scale 15 Detector 17 First bearing 18 Second bearing 20 Bearing mechanism

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kiichiro Nemoto 1-20-1 Sakado, Takatsu-ku, Kawasaki-shi, Kanagawa Prefecture Inside Mitutoyo Corporation (72) Inventor Futa Doi 1-2-1-1, Sakado, Takatsu-ku, Kawasaki-shi, Kanagawa F-term in Mitutoyo Corporation (reference) 2F061 AA02 DD07 DD29 FF07 FF34 FF58 FF72 HH72 JJ67 LL05 SS12 SS14 SS33 VV38 VV48 VV61

Claims (5)

[Claims] 1. A scale having a scale surface indicating a displacement amount and connected to a spindle, and a detector fixed to a measuring device main body and detecting a displacement amount of the scale,
A spindle support structure of a measuring instrument for measuring a dimension or the like of an object to be measured from an axial displacement amount of the spindle, wherein the scale is attached to a scale holder extending in an axial direction of the spindle. The spindle and the spindle are supported by bearings provided at predetermined intervals in the respective axial directions. The bearing supporting the scale holder has two sets of outer circumferences abutting on guided portions on both side surfaces of the scale holder. A spindle support structure for a measuring instrument, comprising a bearing mechanism, wherein each set of bearing mechanisms comprises first and second bearings crossing each other. 2. The spindle support structure of a measuring instrument according to claim 1, wherein the scale surface of the scale and the axis of the spindle are located on the same plane. Construction. 3. The spindle support structure for a measuring instrument according to claim 1, wherein the first and second bearings of each of the sets have their respective opposing surfaces on the measuring instrument main body. A spindle support structure for a measuring instrument, wherein the spindle support structure is supported by a mounted bearing holder. 4. The spindle support structure for a measuring instrument according to claim 1, wherein the bearings supporting the spindles are arranged in parallel with each other and house the spindle therein. A spindle support structure for a measuring instrument, comprising a second linear bush. 5. The spindle support structure for a measuring instrument according to claim 1, wherein a belt drive is connected to the scale holder so as to be rotatable in forward and reverse directions by driving a motor. A spindle support structure for a measuring instrument, wherein the spindle is displaced in the axial direction as the belt drive rotates.