JP2003148566A - Belt driving device and measuring machine using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a belt driving device stabilized in a track of a movable member, and to provide a measuring machine improved in its measurement accuracy. SOLUTION: In this belt driving device comprising a longitudinal X beam 41, an X slider 42 movable along the longitudinal direction of the X beam 41, a pair of pulleys 48, 50 mounted at an interval in the moving direction of the X slider 42, a flat belt 52 hung between the pulleys 48, 50, and a connecting mechanism 53 for connecting the flat belt 52 and the X slider 42, and moving the X slider 42 along the longitudinal direction of the X beam 41 by the driving of the flat belt 52, the connecting mechanism 53 includes a connecting slide mechanism 57 slid approximately in parallel to the rotating shaft direction of the pulleys 48, 50 on a power transmission passage from the flat belt 52 to the X slider 42.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt driving device and a measuring machine using the belt driving device. For example, the present invention relates to a belt driving device that moves a movable member such as a slider along a guide member, and a measuring machine that uses the belt driving device to measure the position and / or coordinates of an object to be measured.

[0002]

BACKGROUND ART A belt drive device that moves a movable member such as a slider along a guide member is known. Such a belt driving device is used, for example, in a three-dimensional measuring machine for measuring the position and / or coordinates of an object to be measured, as disclosed in Japanese Patent Publication No. 4-31525. Conventionally, such a belt driving device has a long guide member 41 and a guide member 41 as shown in FIG. 6 (A).
And a slider driving means 47 for driving the slider 42 along the longitudinal direction of the guide member 41.

The slider driving means 47 includes a guide member 41.
Drive pulley 48 provided on one end side of the guide member 4
1, a driven pulley 50 provided on the other end side, and a flat belt 52 provided on the drive pulley 48 and the driven pulley 50.
And a motor 49 for driving the drive pulley 48. The slider 42 is fixedly fastened to the flat belt 52 with screws 55. Further, for example, an air bearing or the like is provided between the slider 42 and the guide member 41 so that the frictional resistance between the slider 42 and the guide member 41 is suppressed. In such a configuration, when the drive pulley 48 is rotated by the motor 49, the flat belt 52 is rotationally driven via the driven pulley 50. Then, the slider 42 is moved along the guide member 41 by the rotational driving of the flat belt 52.

[0004]

However, the conventional belt drive device has the following problems. When the flat belt 52 is rotationally driven, as shown in FIG. 6B, the flat belt 52 may be rotationally driven while being displaced in the rotation axis direction of the pulleys at the contact surface with both pulleys 48 and 50. is there. When the flat belt 52 moves in the rotation axis direction of both pulleys 48, 50, a force other than the direction guided by the guide member 41 (a force other than the longitudinal direction of the guide member) is applied to the slider 42. If a force is applied to the slider 42 in a direction other than the guided direction, the trajectory of the slider 42 is not stable, and, for example, when the belt drive device is used in a coordinate measuring machine or the like, the measurement accuracy deteriorates. In particular, if an air bearing or the like is provided between the slider 42 and the guide member 41, this effect may be noticeable. Although it is possible to adjust the trajectory of the flat belt 52 by adjusting the inclinations of the driving pulley 48 and the driven pulley 50, it is practically difficult because a high degree of component accuracy and adjustment accuracy are required. Accompany.

Further, when the flat belt 52 is installed, the flat belt 52 may be inclined with respect to the guide member 41. Also in this case, the slider 42 exerts a force (for example, as shown in FIG.
(A) Vertical force) is applied. Therefore, there is a problem that the trajectory of the slider 42 is not stable. On the other hand, arranging the flat belt 52 so as to be exactly parallel to the longitudinal direction of the guide member 41 requires a fine adjustment work, which requires a lot of time and cost.

An object of the present invention is to solve the conventional problems, to provide a belt drive device in which the trajectory of a movable member is stabilized, and to provide a measuring machine in which the measurement accuracy is improved.

[0007]

A belt driving device according to a first aspect of the present invention includes a longitudinal guide member, a movable member provided so as to be movable along the longitudinal direction of the guide member, and the movable member of the movable member. A pair of pulleys arranged at intervals in the moving direction, a belt provided between the pulleys, and a connecting mechanism connecting the belt and the movable member are provided, and the movable member is driven by driving the belt. A belt driving device for moving along the longitudinal direction of the guide member,
The connection mechanism includes a connection slide mechanism that slides in a direction orthogonal to a longitudinal direction of the guide member in a power transmission path from the belt to the movable member.

Here, the direction orthogonal to the longitudinal direction of the guide member means at least one of the rotational axis direction of the pulley and the direction orthogonal to the rotational axis direction and the longitudinal direction of the guide member. In such a configuration, when the pulley is rotated, the belt is rotationally driven via the pulley. Then,
The driving force of the belt is transmitted to the movable member by the connecting mechanism, and the movable member is moved along the longitudinal direction of the guide member. Since it is difficult to adjust the parallelism between the belt and the guide member when the belt is installed, the belt may have an inclination with respect to the guide member. Alternatively, the belt may be displaced in the rotation axis direction of the pulley during rotational driving. Even in such a case, according to the present invention, it is possible to absorb the inclination of the belt with respect to the guide member and the deviation of the belt during rotational driving by sliding the coupling slide mechanism. It can be stabilized along the member.

According to another aspect of the belt drive device of the present invention, a long guide member, a movable member movably provided along the longitudinal direction of the guide member, and a gap in the moving direction of the movable member. A pair of pulleys that are arranged in parallel, a belt that is provided between the pulleys, and a connecting mechanism that connects the belt and the movable member, and drives the belt to move the movable member in the longitudinal direction of the guide member. A belt driving device for moving along, wherein the connecting mechanism is
In the power transmission path from the belt to the movable member, a connecting slide mechanism that slides substantially parallel to the rotation axis direction of the pulley is included.

In such a structure, when the pulley is rotated, the belt is rotationally driven via the pulley. Then, the driving force of the belt is transmitted to the movable member by the connecting mechanism, and the movable member is moved along the longitudinal direction of the guide member. During rotational driving of the belt, the belt may be rotated while being displaced along the contact surface with the pulley in the rotation axis direction of the pulley. Conventionally, since the belt and the movable member are fixedly fastened, the deviation of the belt is transmitted to the movable member, which affects the movement of the movable member. However, in the present invention, since the connecting mechanism that connects the belt and the movable member includes the connecting slide mechanism that slides substantially parallel to the rotation axis direction of the pulley in the power transmission path, the belt rotates the pulley. Even when the belt is displaced in the axial direction, the coupling mechanism slides by the coupling slide mechanism to absorb the displacement of the belt, so that the displacement of the belt is not transmitted to the movable member. As a result, the trajectory of the movable member can be stabilized along the guide member.

A belt driving device according to a third aspect is the belt driving device according to the second aspect, wherein the connecting slide mechanism is a belt side member attached to the belt, the belt side member and the movable member. A guide groove that is provided on either one of the above-mentioned pulleys and is substantially parallel to the rotation axis direction of the pulley, and a fit that is slidably fitted on the guide groove provided on the other of the belt-side member and the movable member. And a collision portion.

According to this structure, when the belt is driven to rotate, the belt side member moves together with the belt. Then, the driving force of the belt is transmitted from the belt-side member to the movable member due to the fitting of the guide groove and the fitting protrusion, so that the movable member is moved along the guide member.
When the belt shifts in the rotation axis direction of the pulley along the contact surface of the pulley, the belt-side member also moves in the rotation axis direction of the pulley together with the belt. Since the guide groove is provided substantially parallel to the rotation axis direction of the pulley, the guide groove and the fitting protrusion can slide in the rotation axis direction of the pulley. Therefore, even if the belt side member is moved in the rotation axis direction of the pulley, the movable member is not subjected to a force in the rotation axis direction of the pulley due to the sliding between the belt side member and the movable member. As a result, the trajectory of the movable member is stabilized along the guide member.

A belt driving device according to a fourth aspect is the belt driving device according to any one of the first to third aspects,
An air bearing is provided between the movable member and the guide member.

With this structure, the frictional force between the movable member and the guide member can be minimized, and the movable member can be moved along the guide member with a light force. Also,
Since it suffices to generate a light force, a motor with a small output can be used even when the pulley is driven by a motor, and cost reduction and noise reduction effect can be expected. Furthermore, by providing the air bearing with rigidity that does not change the film pressure of the air bearing due to the air bearing against the force when the connecting slide mechanism slides, the trajectory of the movable member is stabilized while operating. Performance, cost reduction, and noise reduction can be realized.

A belt driving device according to a fifth aspect is the belt driving device according to any one of the first to fourth aspects,
The belt is a flat belt, and the pulley is a spindle type having a crown on a contact surface with the flat belt.

According to this structure, the flat belt can be always in contact with the crown of the pulley, so that the flat belt can be prevented from being separated from the pulley, and the belt can be reliably driven. The driving force of the flat belt is smaller than that of the V-belt, but if the frictional force between the movable member and the guide member is small due to the air bearing provided between the movable member and the guide member, The driving force of the belt is sufficient. Then, it is possible to provide a belt drive device that uses the quiet and low-noise belt drive that is a feature of the flat belt.

A measuring machine according to a sixth aspect is the measuring instrument according to the first to fifth aspects.
The belt drive device according to any one of 1 to 3 is used to configure a moving mechanism that moves a probe for measuring the position and / or coordinates of the measurement object.

According to this structure, when the movable member moves along the guide member by driving the belt, the probe provided on the movable member comes into contact with the object to be measured. By recording the position of the movable member when the measuring element contacts the measurement target, the position and / or coordinates of the measurement target can be known. Conventionally, since the movable member is fixedly fastened to the belt, the belt is displaced in the rotation axis direction of the pulley, or when the belt is inclined with respect to the guide member, the direction guided by the guide member with respect to the movable member. Other powers were being applied. As a result, the orbit of the movable member was not stable, which also affected the measurement accuracy. However, in the present invention, since the movable member is connected to the belt by the connecting mechanism including the connecting slide mechanism, when the belt is displaced in the rotation axis direction of the pulley or when the belt has an inclination with respect to the guide member. However, since the shift and the inclination are absorbed by the sliding of the connecting slide mechanism, no force is applied to the movable member in the rotation axis direction of the pulley. Therefore, the trajectory of the movable member is stabilized. As a result, the measurement accuracy of the measuring machine is improved.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a belt driving device and a measuring machine using the same according to the present invention will be described below with reference to the drawings. FIG. 1 is an example in which the belt driving device of the present invention is applied to a coordinate measuring machine 1 as a measuring machine. The coordinate measuring machine 1 is configured to include a base 2 on which a measurement target is placed and a moving mechanism that moves the tracing stylus 46. As this moving mechanism, Y that moves the tracing stylus 46 in the Y direction is used. Direction slide mechanism 3 and X direction slide mechanism 4 for moving the tracing stylus 46 in the X direction using a belt drive device.
It has and.

The base 2 is a quadrangular prism having an upper surface that is precision-flattened for placing an object to be measured. For the sake of explanation, two directions orthogonal to each other on the upper surface of the base 2 are referred to as an X direction and a Y direction, respectively, and a direction perpendicular to the upper surface of the base 2 is referred to as a Z direction. The Y-direction slide mechanism 3 is paired with a Y guide rail 31 provided on the base 2 in the Y direction, a Y slider 32R movably provided along the Y guide rail 31, and a Y slider 32R. A Y slider 32L that moves in the Y direction on the base 2, and a column 33 that stands on each of the Y sliders 32R and 32L.
It is configured to include R and 33L. An air bearing is provided between the Y guide rail 31 and the Y slider 32R and between the base 2 and the Y slider 32L, but the description thereof is omitted.

As shown in FIGS. 2 and 3, the X-direction slide mechanism 4 includes an X-beam 41, which is an elongated guide member supported at both ends by columns 33R and 33L, and an X-beam 4.
1. An X slider 42 that is a movable member that is provided so as to be movable along the longitudinal direction of 1, and an X slider that moves the X slider 42.
And a slider drive means 47. The X beam 41 has a long columnar shape, and both ends thereof have columns 33R and 33L.
When the Y-direction sliding mechanism 3 is slid in the Y direction while being supported on the X beam, the X beam 41 is also moved in the Y direction. X
The slider 42 has a ring portion 43 surrounding the periphery of the X beam 41, and the X slider 41 is slidable along the X beam 41 by inserting the X beam 41 into the ring portion 43. . X slider 42
An X slider fitting piece 44, which is a fitting protrusion having a long side in the Y direction, is provided on the upper surface of the above, which will be described later.

An air bearing 45 is provided between the X slider 42 and the X beam 41. In the air bearing 45, the air pad 451 is provided in the Z direction and the Y direction of the X slider 42 (provided so as to sandwich the upper and lower surfaces and the front and rear surfaces of the X beam 41). It is formed by blowing air. The X slider 42 is provided with a tracing stylus 46 so as to hang down toward the base 2 in the Z direction, and the tracing stylus 46 is provided with a Z direction slide mechanism for moving the tracing stylus 46 up and down in the Z direction. Will be omitted in detail.

The X-slider driving means 47 includes an X-beam 41.
Drive pulley 48 provided on one end side of the X beam 41
The driven pulley 50 provided on the other end side of the
8 and the flat belt 52 provided over the driven pulley 50,
Connection mechanism 53 for connecting the X slider 42 and the flat belt 52
With. The drive pulley 48 and the driven pulley 50 are provided on the upper surface of the X beam 41, and the rotation axes of both pulleys 48 and 50 are provided parallel to the Y direction. The drive pulley 48 is provided with a motor 49 for rotating the drive pulley 48. In order to prevent the flat belt 52 from separating from the pulleys 48 and 50, the pulleys 48 and 50 are formed in a spindle shape having a crown 51 on the contact surface with the flat belt 52. Both pulleys 48 and 50 are fixed to the X beam 41 by pulley supporting members 481 and 501 that support the rotating shafts thereof, and a tension bar 411 is provided between the pulley supporting members 481 and 501.

The connecting mechanism 53, as shown in FIG.
The X slider holding portion 54, which is a belt side member fixedly fastened to the lower surface of the flat belt 52 by a screw 55,
The slider 42 is connected to the flat belt 52. The X slider holding portion 54 is provided with a guide groove 56 formed substantially parallel to the Y direction. The X slider fitting piece 44 described above
Are formed so as to fit in the guide grooves 56, and the X slider holding portion 54 is configured to be slidable in the Y direction with respect to the X slider 42. The ball bearing 5 is provided between the X slider holding portion 54 and the X slider fitting piece 44.
8 is provided, and the X slider holding portion 54 is slidable with respect to the X slider fitting piece 44 with low friction. Here, the connecting slide mechanism 57 is connected to the X slider fitting piece 44.
And a guide groove 56.

In such a structure, when measuring the position and / or coordinates of the measurement object, the measurement object is placed on the base 2 and the Y-direction slide mechanism 3 and the X-direction slide mechanism 4 are driven. Then, the tracing stylus 46 is moved to bring the tracing stylus 46 into contact with the object to be measured. Stylus 4 at this time
By recording the positions of 6, the position and / or the coordinates of the measuring object can be measured. When the X-direction slide mechanism 4 is driven, the flat belt 52 is driven to rotate by driving the motor 49 to rotate the drive pulley 48. Then, the X slider holding portion 54 fixed to the flat belt 52 pushes the X slider fitting piece 44 in the X direction, so that the X slider 42 is moved in the X direction along the X beam 41.

While the flat belt 52 is being driven to rotate, as shown in FIG. 5, the flat belt 52 extends along the contact surface with the pulleys 48, 50 in the rotational axis direction of the pulleys 48, 50. It may shift in the (Y direction). At this time, the X slider holding portion 54 shifts in the Y direction together with the flat belt 52. On the other hand, the X slider holding portion 54 has the guide groove 5
6 and the X slider fitting piece 44 slide in the Y direction with respect to the X slider 42, so that the X slider 42 is not moved in the Y direction. Further, since the ball bearing 58 is provided between the X slider holding portion 54 and the X slider fitting piece 44, the X slider holding portion 54 slides with respect to the X slider 42 with low friction,
No force is applied to the slider 42 in the Y direction, and the X slider 4
2 is moved along the X beam 41.

In this embodiment, the X slider 42 is
Since the flat belt 52 is connected via the connecting mechanism 53 having the connecting slide mechanism 57, even when the flat belt 52 is displaced in the Y direction, no force is applied to the X slider 42 in the Y direction. Conventionally, the X slider 42 is the flat belt 5
Since the belt was fixedly fastened directly to the No. 2, when the belt shifts in the Y direction, a force in the Y direction is also applied to the X slider 42, and
The trajectory of the slider was not stable, which affected the measurement of the coordinate measuring machine 1. However, in the present embodiment, the X-slider 42 only transmits the driving force in the X-direction, and does not apply the force in the Y-direction. Therefore, the trajectory of the X slider 42 is stabilized. As a result, the measurement accuracy of the coordinate measuring machine 1 can be improved.

Further, since the connecting slide mechanism 57 is provided, even when the traveling direction of the flat belt 52 has an angle in the Y direction in FIG. 1 with respect to the guide direction of the X beam 41, the connecting slide mechanism 57 is provided. Is slid, the trajectory of the X slider 42 is stabilized along the X beam 41. Therefore, the adjustment process when the flat belt 52 is installed may be simplified, and the cost can be reduced.

In this embodiment, the X beams 41 and X
Since the air bearing 45 is provided between the slider 42 and the slider 42, the frictional force between the X beam 41 and the X slider 42 can be reduced, and the X slider 42 can be moved with a light power. Therefore, since the power of the motor 49 may be small, cost reduction and quiet effect can be expected. Further, since the driving force for moving the X slider 42 may be small, this leads to an advantage that the flat belt 52, which has a small driving force but is quiet and has low noise, can be adopted.

By laying the flat belt 52 over both pulleys 48, 50, tension of the flat belt 52 is applied between the two pulleys 48, 50, and when the flat belt 52 is driven to rotate, The tension generated by the rotation drive is also applied to both pulleys 4
It takes between 8 and 50. Therefore, a force for bending the X beam 41 is generated, but since the tension bar 411 is provided between the pulleys 48 and 50, it is possible to prevent the X beam 41 from bending and to stabilize the trajectory of the X slider 42. You can

The belt drive device of the present invention is not limited to the above-mentioned embodiment, and various modifications can be made without departing from the scope of the present invention. For example, the coupling mechanism 53 that couples the X slider 42 to the flat belt 52 is one of the driving forces of the flat belt 52.
It is only necessary to transmit only the driving force in the X direction to the X slider 42 and not transmit the force in the Y direction to the X slider 42. For example, the X slider holding portion 54 fixedly fastened to the flat belt 52 is provided with a fitting protrusion, and the X slider 4
2 may be provided with a guide groove 56 for guiding the fitting protrusion in the Y direction. Even with such a configuration, when the X slider holding portion 54 is moved in the Y direction, the guide groove 56 is formed.
Since it can slide in the Y direction between the fitting protrusion and the fitting protrusion, no force in the Y direction is applied to the X slider 42.

In this embodiment, a ball bearing 58 is provided between the X slider holding portion 54 and the X slider 42.
However, not limited to the ball bearing 58, various structures such as an air bearing, a roller, and a low friction material can be adopted. In this embodiment, both pulleys 48,
Although 50 is provided on the upper surface of the X beam 41, both pulleys 48 and 50 may be provided on the side surface of the X beam 41. At this time, the coupling mechanism 53 is also provided on the side surface side of the X beam 41, and the X slider 42 and the X slider holding portion 5 are provided.
Although the sliding direction of No. 4 is the Z direction, no problem occurs in the present invention.

Both pulleys 48 and 50 are not directly fixed to the X beam 41, but may be provided on the tension bar 411 provided in parallel with the X beam 41. According to such a configuration, the tension of the flat belt 52 is not applied to the X beam 41, so that it is possible to prevent the situation where the X beam 41 is twisted by the tension of the flat belt 52, and stabilize the trajectory of the X slider 42. be able to. In the present embodiment, an example in which the belt driving device is applied to the coordinate measuring machine 1 has been shown, but the belt driving device of the present invention is not limited to the coordinate measuring machine 1 and various applications are conceivable. For example, one-dimensional measuring machine (height gauge) and two-dimensional measuring machine (surface roughness measuring machine)
Of course, it can be applied to various machine tools that perform precision machining.

In this embodiment, only the connecting slide mechanism that slides substantially parallel to the rotation axis direction of the pulley has been described, but this sliding direction is a direction orthogonal to the longitudinal direction of the guide member (for example, the Z direction in FIG. 1). Or may be slidable in two directions orthogonal to the longitudinal direction of the guide member. Further, the belt is not limited to the flat belt, and may be a V belt, a timing belt, a wire, a chain, or a mixture of these in series or in parallel. In short, any member that can pull the movable member in the longitudinal direction of the guide member may be used. This simplifies the parallel adjustment work of the pulling member with respect to the longitudinal direction of the guide member, which is effective in cost reduction.

[0035]

As described above, according to the belt driving device of the present invention, the track of the movable member is stabilized, and at the same time, the measuring accuracy of the measuring machine using the same is improved. Can play.

[Brief description of drawings]

FIG. 1 is a diagram showing a coordinate measuring machine to which a belt driving device according to an embodiment of the present invention is applied.

FIG. 2 is a front view of the embodiment.

FIG. 3 is a view of the embodiment as seen from above.

FIG. 4 is an enlarged view of a connecting slide mechanism in the embodiment.

FIG. 5 is a diagram showing an operation of the connecting slide mechanism in the embodiment.

FIG. 6 is a diagram showing a belt driving device in the related art.

[Explanation of symbols]

1 three-dimensional measuring machine (measuring machine) 4 X-direction slide mechanism (belt drive device) 41 X beam (guide member) 42 X slider (movable member) 44 X slider fitting piece (fitting protrusion) 45 air bearing 46 probe 48 drive pulley 49 motor 50 driven pulley 51 crown 52 Flat Belt (Belt) 53 Connection mechanism 54 X slider holding part (belt side member) 56 guide groove 57 Connection slide mechanism

Continued front page    (72) Inventor Ayako Kimatsu             2200 Shimoguricho, Utsunomiya City, Tochigi Prefecture             Within Mitutoyo (72) Inventor Seiichi Otsubo             2200 Shimoguricho, Utsunomiya City, Tochigi Prefecture             Within Mitutoyo F-term (reference) 3J049 AA01 BE05 BE06 BE08 BG04                       CA10

Claims (6)

[Claims] 1. A longitudinal guide member, and a movable member provided so as to be movable along the longitudinal direction of the guide member,
A pair of pulleys arranged at intervals in the moving direction of the movable member, a belt provided between the pulleys, and a connecting mechanism that connects the belt and the movable member are provided, and by driving the belt. A belt driving device for moving the movable member along the longitudinal direction of the guide member, wherein the coupling mechanism is in a direction orthogonal to the longitudinal direction of the guide member in a power transmission path from the belt to the movable member. A belt drive device including a connecting slide mechanism that slides to the inside. 2. A longitudinal guide member, and a movable member provided so as to be movable along the longitudinal direction of the guide member.
A pair of pulleys arranged at intervals in the moving direction of the movable member, a belt provided between the pulleys, and a connecting mechanism that connects the belt and the movable member are provided, and by driving the belt. A belt driving device for moving the movable member along a longitudinal direction of the guide member, wherein the coupling mechanism is substantially parallel to a rotation axis direction of the pulley in a power transmission path from the belt to the movable member. A belt drive device including a connecting slide mechanism that slides to the inside. 3. The belt drive device according to claim 2, wherein the coupling slide mechanism includes a belt side member attached to the belt, and one of the belt side member and the movable member rotates the pulley. A guide groove formed substantially parallel to the axial direction; and a fitting projection provided on the other of the belt-side member and the movable member and slidably fitted into the guide groove. Belt drive device. 4. The belt driving device according to claim 1, wherein an air bearing is provided between the movable member and the guide member. 5. The belt driving device according to claim 1, wherein the belt is a flat belt, and the pulley is a spindle shape having a crown on a contact surface with the flat belt. Characteristic belt drive device. 6. A moving mechanism for moving a tracing stylus for measuring the position and / or coordinates of an object to be measured, using the belt driving device according to claim 1. Measuring machine characterized by.