JP6717762B2 - Belt measuring device - Google Patents

Description

The present invention relates to a measuring device for measuring the dimensions of various parts of a transmission belt.

A general measuring device for measuring the dimensions of each part of a transmission belt is provided with a fixed-side drive pulley and a movable-side driven pulley, and a transmission belt (endless belt) hung between the pair of pulleys. After the driven pulley is moved to a belt-like belt (hereinafter referred to as a belt) to give a predetermined tension, the belt is acclimated to run and the dimensions of each part of the belt are measured.

Conventionally, as a belt measuring device that applies a predetermined tension to a belt, a weight is suspended via a shaft (hereinafter, a driven shaft) to which a driven pulley is attached, and a predetermined measuring load is applied to the belt. A method (hereinafter, dead weight method) is representative (for example, Patent Document 1).

In addition, in recent belt measuring devices, in addition to measuring the length of the belt, measurement items such as width, thickness, warpage, meandering amount, tooth pitch of toothed belt, ride-out of V belt, etc. And its measurement technology is diversified.

Further, conventionally, a so-called shift belt, which is a low-edge cog type V belt (including a double cog type) and is used in a belt type continuously variable transmission, has been positively used in a transmission having a small pulley diameter. However, misalignment occurs due to gear shifting operation, and a large compressive force is applied to the side surface of the belt, so that it is required to further improve lateral pressure resistance and bending fatigue resistance. Therefore, when the target belt is a speed change belt, it is important in product design to accurately evaluate the mutual relationship of belt characteristics such as bending rigidity, lateral rigidity of the belt, and friction coefficient with the pulley. As for the lateral rigidity of the belt, the ride-out is measured by a belt measuring device or the like as a substitute characteristic.

Ride-out (RO) is a dimensional value defined by the length from the back surface (outer peripheral surface) of the belt to the outer peripheral surface of the pulley, and is a dimensional value directly related to the amount of the belt dropped into the pulley V groove portion. Therefore, it largely depends on the load (hereinafter, load) applied to the running belt.

During traveling of the belt, a load corresponding to the characteristics of the load connected to the driven shaft always acts on the belt, and the fluctuation of the load is directly connected to the fluctuation of the ride out of the belt. Therefore, in the belt measuring device for measuring the ride-out, the load cell is the base of the load, and the load acting on the driven shaft due to the belt tension during traveling (hereinafter referred to as the dynamic shaft load) is It is required to have both the function of accurately detecting with a detector), displaying and outputting the measured value, and the function of accurately controlling the dynamic shaft load so as to match the target dynamic shaft load. ing.

In this respect, in the dead weight method disclosed in Patent Document 1, the fine control of the dynamic axial load and the correspondence to the extremely large dynamic axial load (for example, 3000N) which may be requested by the user in some cases are device structures. It is difficult to move the driven shaft linearly by rotating the ball screw with a prime mover such as a servo motor, and based on the measured value of the dynamic shaft load from the load cell, the moving distance (inter-axis distance) of the driven shaft can be calculated. A method (hereinafter, ball screw type) of applying a target dynamic shaft load to a driven shaft by adjusting has been studied in a belt measuring device.

JP 2001-241922 A

However, in the case of the ball screw type, in the process of applying a predetermined dynamic shaft load to the driven shaft using the ball screw mechanism, if any of the following (1) to (3) is satisfied, the belt is pretensioned. The value of the increase amount (ΔL) of the inter-axis distance after application is small. (1) Belt with a high spring constant (Kb): A belt with a higher spring constant (Kb) has an increased amount of axial distance (ΔL) at the same load (F) than a belt with a low spring constant (Kb). The value of) becomes small (from Kb=F/ΔL). (2) Belt with shorter circumference: A belt with a shorter circumference has a smaller value of the increase amount (ΔL) of the axial distance under the same load (F) than a belt with a longer circumference. (3) Small load (F): The smaller the load (F), the smaller the increase in axial distance (ΔL) compared to when the load (F) is large (Kb=F). / From ΔL).
In other words, in the process of applying a predetermined dynamic shaft load to the driven shaft using the ball screw mechanism, if the increase in the axial distance after applying the pretension to the belt is relatively small, the driven shaft is slightly driven in the loosening direction. The load F may drop out just by moving the shaft, or the load F may be excessive by just moving the shaft a little. For this reason, it becomes difficult to control the fine movement of the driven shaft in order to accurately match the target dynamic shaft load range, and the applied load and belt tension applied to measure the dimensions of each part such as the rideout range are within the target range. There was a case to get out of.

As described above, even in the ball screw type belt measuring device, in the process of applying a predetermined dynamic shaft load to the driven shaft by using the ball screw mechanism, the axial distance after the pretension is applied to the belt is reduced. If the amount of increase is relatively small, it becomes difficult to finely control the amount of movement (movement distance) of the driven shaft, and there is a problem that the target dynamic shaft load cannot be accurately applied to the driven shaft. For this reason, the dynamic axial load is continuously changed in multiple steps by one operation, and corresponding changes in the dimensions of each part such as the ride out of the belt are grasped to lead to the evaluation of the belt characteristics such as the lateral rigidity of the belt. That was an even more difficult problem.

Therefore, an object of the present invention is to provide a predetermined dynamic shaft load to a driven shaft by using a ball screw mechanism even if the increase in the axial distance after applying pretension to the belt is relatively small. Another object of the present invention is to provide a belt measuring device that enables easy control of the moving amount (moving distance) of the driven shaft and that can apply a target dynamic shaft load to the driven shaft with high accuracy.

According to the present invention, a belt is wound around a drive pulley provided on a main shaft and a driven pulley provided on a driven shaft, and the driven shaft is moved in a stretching direction of the belt so that a predetermined dynamic force is generated with respect to the driven shaft. A belt measuring device that measures the dimensions of each part of the belt that has been run with an axial load applied,
A moving part provided on the driven shaft,
A ball screw mechanism for moving the moving portion in the stretching direction of the belt according to the movement of the ball screw nut screwed to the ball screw;
Urging means provided at the connecting portion between the moving portion and the ball screw mechanism, having a spring constant smaller than the spring constant of the belt, and applying a repulsive urging force to the driven operation of the moving portion,
A load cell that is provided in the moving unit and detects a dynamic shaft load with respect to the driven shaft,
Based on an electric signal from the load cell, a calculation control unit that calculates a measured value of the dynamic shaft load with respect to the driven shaft,
A belt measuring device, comprising: a display unit for numerically displaying a measured value of the dynamic shaft load with respect to the driven shaft calculated by the calculation control unit.

According to the above configuration, the urging means that applies the repulsive urging force to the driven operation of the moving unit has a spring constant smaller than the spring constant of the belt to be stretched, so that the driven shaft moves in the stretching direction. The operation can be a moving operation to which the repulsive biasing force of the biasing means is added. As a result, the moving distance of the ball screw nut in the ball screw mechanism can be made longer than the moving distance of the driven shaft (moving portion).
For this reason, in the process of applying a predetermined dynamic shaft load to the driven shaft using the ball screw mechanism, the connecting portion between the moving portion and the ball screw mechanism is not provided with a biasing means (the moving portion and the ball screw mechanism are directly connected to each other. Compared with the configuration described above), it is possible to reduce the moving distance of the driven shaft (moving portion) with respect to the moving distance of the ball screw nut in the ball screw mechanism.
That is, even when the increase in the axial distance after applying the pre-tension to the belt is relatively small, it becomes easy to finely control the moving distance (axial distance) of the driven shaft, resulting in a small dynamic axial load. The control is also easy, and the target dynamic shaft load can be accurately applied to the driven shaft without the load being removed or the load being excessively applied by the movement operation of the driven shaft.
Further, it is possible to grasp the difference from the target dynamic axial load based on the numerically displayed measured value of the dynamic axial load. Thereby, the measured value of the dynamic shaft load is kept within the range of the target dynamic shaft load by finely adjusting or controlling the moving distance (inter-axis distance) of the driven shaft by the ball screw mechanism based on the difference. be able to.

Further, the present invention is the belt measuring device, wherein the moving member has a pair of opposing members that receive the repulsive biasing force of the biasing means,
The urging means has a first urging means and a second urging means,
The first urging means and the second urging means are arranged between the pair of opposing members with a bracket portion fixed to a ball screw nut of the ball screw mechanism being sandwiched between them so as to be separated from each other in the tension direction. Further, both ends of the first urging means and the second urging means are arranged in a free state,
The arithmetic control unit equalizes the measured value of the dynamic shaft load with respect to the driven shaft to the weight of the moving unit when the first urging unit and the second urging unit are set in a free length state. The belt measuring device is characterized by executing the arithmetic control.

According to the above configuration, the repulsive biasing force can be applied to the moving operation of the moving unit in response to a wider range of load due to the following reasons 1) to 3). As a result, in the process of applying a predetermined dynamic shaft load to the driven shaft using the ball screw mechanism, even if the amount of increase in the axial distance after the pretension is applied to the belt is relatively small, a wider range of load is applied. It becomes easy to finely control the movement distance (inter-axis distance) of the driven shaft in accordance with the load, and the target dynamic shaft load can be accurately applied to the driven shaft.

1) Since the first urging means and the second urging means are arranged between the pair of opposing members with the bracket portion fixed to the ball screw nut of the ball screw mechanism being sandwiched between them, the first urging means and the second urging means are separated from each other in the stretching direction. (A) When the dynamic axial load is less than the weight of the moving part (the total weight of the part suspended by the belt), at least the urging force of the belt in the stretching direction (hereinafter, simply referred to as the stretching direction) is applied. The means (first urging means) can be compressed and deformed to support the weight of the moving portion and give a repulsive urging force to the moving operation of the moving portion. (B) When the dynamic axial load exceeds the weight of the moving portion (total weight of the portion suspended by the belt), at least the biasing means (second biasing means) on the tension side in the stretching direction is compressed and deformed. Thus, a repulsive biasing force can be applied to the moving operation of the moving unit.
On the other hand, when the urging means are not arranged apart from each other in the stretching direction by sandwiching the bracket part fixed to the ball screw nut of the ball screw mechanism between the pair of opposing members (in either one of the stretching directions). The effect that the target dynamic shaft load can be accurately applied to the driven shaft is that if the biasing means is arranged only on the loose side in the tension direction from the bracket part, the dynamic shaft weight equal to or less than the moving part weight When the biasing means is limited to the load range and is arranged only on the tension side in the tension direction with respect to the bracket portion, the dynamic shaft load range is equal to or more than the weight of the moving portion.

2) Both ends of the first urging means and the second urging means are not in a free state, and both ends of the first urging means and the second urging means are bracket portions (both surfaces in the tension direction) and/or When it is fixed to the opposing member, when one biasing means in the stretching direction is compressed and deformed to apply a repulsive biasing force to the movement of the driven shaft, tensile stress is applied to the other biasing means in the stretching direction. Since the urging force is applied in the moving direction of the driven shaft, the repulsive urging force that should be applied to the movement of the driven shaft is weakened. Therefore, when both ends of the first urging means and the second urging means are in the free state, it is more reliable than when both ends of the first urging means and the second urging means are not in the free state. The repulsive biasing force can be applied to the moving operation of the moving unit.

3) When the first urging means and the second urging means are set to a free length (an urging state in which the repulsive urging force does not reach the moving operation of the moving part), the measured value of the dynamic shaft load is set to the moving part. When the arithmetic control is performed so as to be equal to the weight of the moving weight, the weight of the moving portion (weight on the spring, so-called tare, so to speak) is surely obtained as in a known counterbalance mechanism (for example, Japanese Unexamined Patent Publication No. 2002-257501) in a dead weight type measuring machine. It has the effect of being able to reset the zero point of (weight). This allows the range of dynamic axial loads to start from zero.

In the belt measuring device, the first urging means and the second urging means are coil springs.
A guide shaft is fixed between the pair of opposing members,
In the belt measuring device, the coil spring of the first biasing means and the coil spring of the second biasing means sandwich the bracket portion and are inserted into the guide shaft.

According to the above configuration, since the guide shaft fixed between the pair of opposing members is passed through the inside of the coil winding of the coil spring, it is possible to simply realize a device configuration in which the coil spring does not fall off. it can.

In the belt measuring device of the present invention, each of the first urging means and the second urging means has its both ends substantially in contact with the bracket portion and the facing portion when in a free length. The belt measuring device is characterized by being

According to the above configuration, the repulsive urging force of the first urging unit and the second urging unit moves from the state in which the repulsive urging force of the first urging unit and the second urging unit does not reach the movement operation of the moving unit. It is possible to make a transition to a state in which the movement of the parts is reached without any interruption. In other words, the movement operation of the driven shaft (moving portion) using the ball screw mechanism can be operated continuously with almost no interruption.

Further, in the belt measuring apparatus according to the present invention, the ball screw mechanism has a prime mover that controls movement of the ball screw nut screwed to the ball screw.
The arithmetic control unit, based on the difference between the measured value of the dynamic shaft load and the preset value of the dynamic shaft load input in advance, for the movement operation of the ball screw nut screwed to the ball screw by the prime mover. The belt measuring device is characterized by executing feedback control.

According to the above configuration, in the process of applying a predetermined dynamic shaft load to the driven shaft by using the ball screw mechanism, even if the amount of increase in the axial distance after applying the pretension to the belt is relatively small, The moving distance (inter-axis distance) of the driven shaft can be finely controlled by automatic operation so as to be within the range of the dynamic shaft load, and the target dynamic shaft load can be accurately applied to the driven shaft.
Furthermore, by setting and registering multiple operation patterns and steps (order) consisting of a combination of dynamic shaft load and other conditions (driving pulley rotation speed, ambient temperature) as an operation program in advance, the operation can be performed by one operation. Even if you perform automatic operation that continuously changes the dynamic axial load in multiple stages (from small load to large load), you can measure changes in the dimensions of each part such as the rideout of the belt between each step without any problems. It can be connected to the evaluation of the belt characteristics such as the lateral rigidity.

In the process of applying a predetermined dynamic shaft load to the driven shaft using the ball screw mechanism, the amount of movement (movement) of the driven shaft (movement) It is possible to provide a belt measuring device in which fine control of the distance) is easy and a target dynamic shaft load can be accurately applied to the driven shaft.

It is the front view and right side view of the belt measuring device concerning this embodiment. It is an enlarged view of a frame including a biasing means of the belt measuring device according to the present embodiment. It is explanatory drawing of a drive pulley and a driven pulley which concern on this embodiment. It is explanatory drawing of the bracket part which concerns on this embodiment. It is explanatory drawing of the belt which concerns on this embodiment. It is explanatory drawing of the driving condition of the driving pattern 1 which concerns on this embodiment. It is an automatic driving|operation operation|movement flow which concerns on application of a dynamic axial load and measurement of ride-out after automatic driving start. It is explanatory drawing which shows the state of the biasing means in axial load 0N. It is explanatory drawing which shows the state of the urging means in dynamic axial load 300N. It is explanatory drawing which shows the state of the urging means in dynamic axial load 700N. It is explanatory drawing which shows the state of the urging means in dynamic axial load 1000N. It is explanatory drawing which shows the measurement position of the ride out (RO) of a belt. It is the schematic of the belt measuring device which concerns on a comparative example. It is a graph which shows the level (difference) of the display value and test value of the axial load of an Example, and the level (difference) of the display value and test value of the axial load of a comparative example. It is a schematic diagram of the biasing means concerning other embodiments.

(Belt measuring device 1)
The belt measuring device 1 according to the present invention will be described.
As shown in FIGS. 1 and 2, the belt measuring device 1 winds the belt 10 between the drive pulley 2 provided on the main shaft 21 and the driven pulley 3 provided on the driven shaft 31, and the driven shaft 31 is attached to the belt 10. It is possible to measure the size of each part of the belt 10 which is moved in the stretching direction and is caused to travel with a predetermined dynamic axial load applied to the driven shaft 31.

As shown in FIG. 3, the driving pulley 2 and the driven pulley 3 can be selected from any one of the basic S, M, and L precision-machined pulleys having different upper widths, outer diameters, and groove depths. There is. Table 1 shows each basic size of the S size drive pulley 2 and the driven pulley 3 according to the present embodiment.

As shown in FIG. 1, the belt measuring device 1 of the present embodiment is a vertical belt measuring device 1 and is a measuring device that measures the ride-out of a belt 10, which is a speed change belt. Especially, the amount of change in the rideout when the load is continuously changed in multiple steps within the load range required for the speed change belt is accurately grasped to evaluate the belt characteristics such as lateral rigidity of the speed change belt. It is a measuring instrument that can be connected. Here, the ride-out (RO) is a dimension defined by the length (distance in the belt thickness direction) from the back surface (outer peripheral surface) of the belt 10 to the outer peripheral surface (reference point shown in FIG. 12) of the drive pulley 2. It is a value.

As shown in FIGS. 1 and 2, the belt measuring device 1 according to the present embodiment is movable in a vertical direction (a direction in which the belt 10 is stretched) with respect to a main shaft 21 fixed to a housing 11. A driven shaft 31, a moving portion 4 provided on the driven shaft 31, a ball screw mechanism 5, an urging means 6 provided at a connecting portion between the moving portion 4 and the ball screw mechanism 5, and an interposing device on the moving portion 4. The load cell 43 detects the dynamic shaft load on the driven shaft 31, and the PC 17 including the arithmetic control unit 171 and the display unit 172. The main shaft 21 is rotated by the rotational drive of the drive motor 32 being transmitted. The drive motor 32 is an electric geared motor, and is rotationally driven corresponding to a rotation speed of 50 to 360 rpm.

(Moving part 4)
The moving unit 4 includes a driven base 41 (including a linear guide block 49) fixed to the driven shaft 31, a load base 42, a load cell 43 interposed between the driven base 41 and the load base 42, and a load base 42. It comprises a fixed frame 44. Two linear guide rails 19 for slidingly supporting the driven base 41 and the load base 42 in the vertical direction (belt stretching direction) are provided in the housing 11 in parallel. As a result, the driven shaft 31 including the driven pulley 3 and the moving portion 4 move in the vertical direction (the direction in which the belt 10 is stretched), specifically, in the loose side (upward direction) of the belt 10 and the tension of the belt 10. It is provided to be movable to the side (downward).

The load cell 43 is a load detector, and in the case of the present embodiment, the strain gauge attached to the surface of the load cell 43 detects the dynamic shaft load or the moving part weight and converts it into an electric signal. As the load cell 43, a compression/tension dual-use load cell model U3B1-500K-B manufactured by Minebea Co. is used. The rated capacity is 4903 N (500 kgf), and it is possible to support a wide range of shaft load of 200 N to 3000 N. Here, the dynamic shaft load is a load that acts on the driven shaft 31 due to the tension of the running belt 10, and is an index of a load that is a load applied to the running belt. Further, the moving portion weight refers to a total weight of the constituent members suspended on the belt 10 and corresponds to a so-called sprung weight. Specifically, the moving part weight is a member including the driven pulley 3, the driven shaft 31, the driven base 41 (including the linear guide block 49), the load cell 43, the load base 42, the frame 44, the urging means 6, and the like. Is the total weight of.

Further, the wire of the wire encoder 16 is attached to the driven base 41 as shown in FIG. By measuring the pulling amount of the wire of the wire encoder 16 in the vertical direction (stretching direction), the axial distance between the main shaft 21 and the driven shaft 31 that changes with the vertical movement of the moving unit 4 is measured. ..

(Ball screw mechanism 5)
As shown in FIGS. 1 and 2, the ball screw mechanism 5 is mainly fixed to a ball screw 53 in which a spiral thread groove is formed on a shaft, a ball screw nut 51 screwed into the ball screw 53, and a ball screw nut 51. The bracket portion 52, a prime mover 54 for axially rotating the ball screw 53, and a speed reducer 55 (including a timing belt) for controlling the drive of the prime mover 54.

As shown in FIG. 4, the bracket portion 52 has a substantially rectangular parallelepiped outer shape, and is machined from flat steel (thickness: about 30 mm). Further, in the bracket portion 52, for inserting a hole portion 52c (inner diameter 50 mm) penetrating in the tension direction (vertical direction) for fixing to the ball screw nut 51, and two guide shafts 443a and 443b described later. Two slide bearing fixing holes 52a and 52b (each having an inner diameter of 12 mm) are provided in parallel. Then, a ball screw nut 51 (outer diameter 50 mm) is press-fitted into the hole 52c, and slide bearings 52d and 52e (outer diameter 12 mm) are press-fitted into the two slide bearing fixing holes 52a and 52b, respectively. Has been done.

For the slide bearings 52d and 52e, oilless bush model number MPBZ8-15 manufactured by MISUMI is used. The slide bearings 52d and 52e have a cylindrical shape with an inner diameter of 8 mm and an outer diameter of 12 mm, and a solid lubricant is embedded in a brass alloy. This is fixed by press fitting into the two slide bearing fixing holes 52a and 52b provided in the bracket portion 52.

In the ball screw mechanism 5, the ball screw 53 can be axially rotated by the rotational movement of the prime mover 54 to linearly move the bracket portion 52 fixed to the ball screw nut 51 screwed into the screw groove of the ball screw 53 up and down. ..

The prime mover 54 employs a servo motor. By using the prime mover 54 as a servomotor, feedback control (rotation ON, rotation OFF, based on the difference between the measured value of the dynamic shaft load based on the detection signal from the load cell 43 and the preset value of the dynamic shaft load, The rotation direction, etc.) can be precisely adjusted (details will be described later). Further, the prime mover 54 may be a stepping motor that operates by digital control from the arithmetic control unit 171 of the PC 17 instead of feedback control.

In the present embodiment, the prime mover 54 is an electric servomotor of HG-KR13 manufactured by Mitsubishi Electric Corporation. In this electric servomotor, the ball screw 53 is axially rotated to move the ball screw nut 51 both in the stretching direction (up and down). Thereby, the driven shaft 31 can be moved in both the stretching directions (up and down) via the bracket portion 52 and the biasing means 6 which will be described later. The electric servomotor performs feedback control (rotation ON, rotation OFF, and rotation direction feedback) based on the difference between the measured value of the dynamic shaft load based on the detection signal from the load cell 43 and the preset value of the dynamic shaft load input in advance. Controlled). The rotation speed of the electric servomotor is substantially constant corresponding to the guideline of the moving speed of the driven shaft 31 (for example, 0.15 to 0.5 mm/sec, 0.5 mm/sec in the automatic operation of the embodiment). It is controlled by the rotation speed. The reduction ratio of the speed reducer 55 is 20, and the lead of the ball screw 53 is 6 mm.

(Frame 44 including urging means 6)
As shown in FIG. 2, the frame 44 fixed to the load base 42 has a substantially U-shape when viewed from the front, and is opposed to each other at both ends in the stretching direction (vertical direction) of the frame 44 in the stretching direction. And a pair of upper facing members 441 and lower facing members 442 (opposing surfaces). Then, between the upper facing member 441 and the lower facing member 442, two guide shafts 443a and 443b are fixed so as to be parallel to the stretching direction (vertical direction). The slide bearings 52d and 52e of the bracket portion 52 are inserted through the two guide shafts 443a and 443b. Accordingly, the bracket portion 52 is movable in the stretching direction (vertical direction).

Further, on the two guide shafts 443a and 443b, the upper spring 61a and the upper spring 61b are inserted between the upper facing member 441 and the bracket portion 52, respectively, and the lower facing member 442 and the bracket portion 52 are connected. The lower spring 62a and the lower spring 62b are respectively inserted between them. That is, the upper spring 61a (upper spring 61b) and the lower spring 62a (lower spring 62b) have the bracket portion 52 fixed to the ball screw nut 51 of the ball screw mechanism 5 between the upper facing member 441 and the lower facing member 442. They are sandwiched and are separated from each other in the stretching direction (vertical direction).

As the upper spring 61a (upper spring 61b) and the lower spring 62a (lower spring 62b) as the urging means 6, compression coil springs that are elastically deformable when receiving a compressive load are used. The material of the upper spring 61a (upper spring 61b) and the lower spring 62a (lower spring 62b) is an oil temper wire for springs. Further, both ends of the upper spring 61a (upper spring 61b) and the lower spring 62a (lower spring 62b) are ground to make them substantially flat in the direction perpendicular to the central axis for better installation. Specifically, as the upper spring 61a (upper spring 61b), a coil spring (right-handed: the cross-section is rectangular) model SWM20-50 manufactured by MISUMI is used. The specifications of the upper spring 61a (upper spring 61b) are a spring outer diameter of 20 mm, a spring inner diameter of 10 mm, a spring free length of 50 mm, a spring constant of 49.0 N/mm, an allowable deflection rate of 32%, and a maximum load of 784 N (80 kgf). As the lower spring 62a (lower spring 62b), a coil spring (right-handed: the cross section of the wire is rectangular) model SWB20-150 manufactured by MISUMI is used. The specifications of the lower spring 62a (lower spring 62b) are a spring outer diameter of 20 mm, a spring inner diameter of 10 mm, a spring free length of 150 mm, a spring constant of 52.3 N/mm, an allowable deflection rate of 30%, and a maximum load of 1568 N (160 kgf). By using the upper spring 61a and the upper spring 61b and the lower spring 62a and the lower spring 62b, it is possible to cope with the maximum load of 300 kgf (equipment requirement).

Here, the urging means 6 (98 N/mm for two upper springs 61a and 61b that act at the time of application when the dynamic axial load is less than 700N, and two lower springs 62a and 62b that act at the time of application when the dynamic axial load exceeds 700N are used. The spring constant of about 105 N/mm is smaller than that of the belt 10 (about 200 N/mm in this embodiment).

Further, in the present embodiment, both ends of the upper spring 61a (upper spring 61b) are not fixed to the upper facing member 441 and the bracket portion 52, but are inserted into the guide shaft 443a (guide shaft 443b) in a free state. There is. Similarly, both ends of the lower spring 62a (lower spring 62b) are not fixed to the bracket 52 and the lower facing member 442, but are inserted into the guide shaft 443a (guide shaft 443b) in a free state. Further, the upper spring 61a (upper spring 61b) is dimensioned such that both ends of the upper spring 61a (upper spring 61b) substantially contact the upper facing member 441 and the bracket portion 52 when the upper spring 61a (free upper length) has a free length. Similarly, the lower spring 62a (lower spring 62b) is sized such that both ends of the lower spring 62a (lower spring 62b) substantially contact the bracket portion 52 and the lower facing member 442 when in free length.

(Ride-out measuring device 14)
As shown in FIG. 1, the ride-out measuring device 14 includes a pair of light emitting and receiving portions arranged so as to sandwich the belt 10 wound around the drive pulley 2 in a direction orthogonal to the main shaft 21 so as to sandwich the drive pulley 2 from both sides. A laser micrometer 141 (a non-contact precision measuring device by laser scanning of a light emitting and receiving device) and a laser marker 142 are mainly used. Note that the configuration and the ride-out measurement method are substantially the same as the disclosure content of Patent Document 1. The ride-out measuring device 14 measures the ride-out (RO) of the belt 10.

As the laser micrometer 141, a laser micrometer model 3Z4L-S506RV3 manufactured by OMRON Corporation is used. The laser micrometer 141 and a laser marker 142 for spot laser irradiation for aiming the laser beam at a target measurement point are suspended from a pair of rails provided on the frame structure above the drive pulley 2. It is provided on the moving table 143 that is locked to. The moving base 143 is movable in the width direction of the belt 10 (axial direction of the drive pulley 2).

(PC17)
The PC 17 is a personal computer including an operation panel (touch panel, not shown), a calculation control unit 171, and a display unit 172. The arithmetic control unit 171 calculates the electric signal of the dynamic axial load detected by the load cell 43 into a measured value of the dynamic axial load, and causes the display unit 172 including a liquid crystal screen capable of digital display to numerically display it. The arithmetic control unit 171 also executes data output (digital), recording, control (feedback, etc.), and monitoring (monitoring).

(Constant temperature bath 12)
The constant temperature bath 12 includes a heat insulating enclosure (including a heat resistant glass door) between the drive pulley 2 and the driven pulley 3, a hot air blower 121, a temperature sensor, and the like. When the atmospheric temperature in the constant temperature bath is set and registered on the operation panel of the PC 17 to an arbitrary temperature within the range of 25° C. (room temperature) to 130° C., the temperature controller raises and maintains the set temperature.

(Belt 10)
In the belt 10, as shown in FIG. 5, a core wire 103 made of a fiber cord is embedded in an adhesive rubber layer 102, an extension layer 105 including a reinforcing cloth 104 is provided on an upper portion of the adhesive rubber layer 102, and a lower portion is provided on a lower portion thereof. Similarly, a compression layer 107 including a reinforcing cloth 106 is arranged. Cog troughs 108 and cog ridges 109 are alternately formed on the compression layer 107 at predetermined intervals along the belt circumferential direction. The belt 10 is a low edge cog type V belt and is a speed change belt. Further, the surface (outer peripheral surface) of the reinforcing cloth 104 is flat without any convex portion (cog portion). The spring constant of the belt 10 used was about 200 N/mm.

(Automatic driving procedure for belt ride-out measurement)
Next, an automatic operation procedure for measuring the rideout of the belt 10 using the belt measuring device 1 will be described.

(1) On the operation panel (touch panel, not shown) of the PC 17, a load step (maximum step number 20), a rotation speed step (maximum step number 20), a temperature step (maximum step number 2), a ride-out measurement step (maximum step) A plurality of operation patterns, which is a combination consisting of Equation 20), is registered.

(2) Select any one of a plurality of registered operation patterns (operation pattern 1 in the present embodiment) on the operation panel of the PC 17, and select operation conditions (axial load, drive shaft speed, ambient temperature), The number of cycles (the number of times of ride-out measurement), the outer peripheral length (BOC) of the target belt, the number of load steps, the pulley size (S, M, L), etc. were input (see FIG. 6). As shown in FIG. 6, the axial load (dynamic axial load) as an operating condition was applied from 200 N to 1200 N in 10 steps (10 steps). Here, the pretension initially applied to the belt 10 is 200N. Further, the moving speed of the driven shaft 31 set as a guide is 0.5 mm/sec.

(3) By changing the basic size of the pulley, the following zero point reset operation of the moving part weight was performed. The zero-point resetting operation of the moving part weight usually changes the basic size of the driven pulley 3 because the moving part weight changes depending on the basic size of the driven pulley 3 (3 sets of S, M and L) used. This is an operation that is executed only in the case of the above, and is an operation that allows the range of the dynamic shaft load to be started from zero in advance.

Specifically, the following operation is performed as an unsteady work only once when the actual weight of the moving portion 4 is changed, such as when the driven pulley 3 is changed to a completely new size. As a routine work for changing the driven pulley 3 to another basic size, only the following zero resetting operation of the moving portion weight may be performed.

First, the weight of the moving section including the driven pulley 3 is measured for each size of the driven pulley 3. Therefore, a test load cell (model SLBL-5KN rated capacity 5KN manufactured by Shimadzu Corp.) is set between the main shaft 21 and the driven shaft 31 via a connecting tool, and the repulsive urging force by the urging means 6 is applied to the moving part 4. Is adjusted by the ball screw mechanism 5 so that it does not affect the movement operation of (1) (the upper springs 61a and 61b and the lower springs 62a and 62b have free lengths). The removed driven pulley 3 is attached to an arbitrary part of the moving portion 4.

The weight of the moving part in this state is measured for each pulley size by the above-mentioned test load cell. The zero point resetting operation of the moving part weight is performed by mounting the driven shaft 31 of the same size as the basic size of the driven shaft 31 input on the operation panel to the driven shaft 31 and not loading the belt 10 on the operation panel. Complete by pressing the "Movement weight zero point reset button".

For example, when the basic size of the driven pulley 3 is S and the measured value of the moving portion weight by the verification load cell is 700N, the zero point reset operation of the moving portion weight is performed by inputting the driven shaft 31 to the driven panel. When the driven pulley 3 of the same size as the basic size of the pulley 3 is attached and the belt 10 is not mounted and the value based on the electric signal from the load cell 43 is -700 N, the measured value of the axial load (display value ) Is 0 (zero) N, the arithmetic control unit 171 performs arithmetic processing.

As a result, when the repulsive urging force of the urging means 6 does not reach the moving operation of the moving portion 4 (both the upper springs 61a and 61b and the lower springs 62a and 62b are free length), the measured value of the dynamic shaft load is It becomes equal to the moving part weight (700N).

(4) Next, the driven pulley 3 was moved to a predetermined position (position where the inter-axis distance was shortened), and then the belt 10 was stretched between the drive pulley 2 and the driven pulley 3.

(5) By pressing the start button on the operation panel, the driven pulley 3 is pushed down by an automatic operation so that the belt 10 mounted on the belt is not loosened, and the drive pulley 2 remains in a non-rotating state and the belt is pretensioned (200 N). Is given.

(6) After that, the drive pulley 2 is rotated so that the belt 10 travels between the drive pulley 2 and the driven pulley 3.

(7) In accordance with the operation pattern input in (2) above, control is performed to continuously change the conditions such as the dynamic shaft load in multiple stages, and the belt 10 is operated under the respective conditions such as the dynamic shaft load. The ride-out is automatically measured by the ride-out measuring device 14, and the data is output after the driving is completed.

Next, with reference to FIG. 7, an automatic driving operation flow relating to (7) application of a dynamic axial load and measurement of rideout after the start of automatic driving will be described.

First, the operation pattern input in (2) above is called (S1). In this embodiment, the operation pattern 1 is read.

Next, the step operation based on the operation pattern called in S1 is started (S2). In this embodiment, the step operation based on the operation pattern 1 shown in FIG. 7 is started. First, the operation in step 1 (axial load 200N) is started. After that, the step operation proceeds according to the process of S9 described later.

After the start of the step operation, the arithmetic control unit 171 of the PC 17 measures the dynamic axial load on the driven shaft 31 measured by the load cell 43 and the set value of the axial load corresponding to each step of the operation pattern 1 (pre-input). It is determined whether the difference between the dynamic shaft load and the set value) is within ±3% (S3). For example, if the measured value of the dynamic shaft load on the driven shaft 31 is 193 N and the set value of the shaft load corresponding to step 1 is 200 N in the step 1 of the operation pattern 1, (193-200)/ 200=−0.035=−3.5%, and it is determined that the difference is not within ±3%. On the other hand, in the step 5 of the operation pattern 1, if the measured value of the dynamic shaft load on the driven shaft 31 is 606N and the set value of the shaft load corresponding to step 5 is 600N, (606-600)/ 600=0.01=1%, and it is determined that the difference is within ±3%.

If the difference is not within ±3% in the process of S3 (S3: NO), then the arithmetic control unit 171 determines whether or not the difference exceeds +3% (S4). If the difference exceeds +3% (S4: YES), the difference between the measured value of the dynamic shaft load on the driven shaft 31 and the set value of the shaft load corresponding to each step of the operation pattern 1 is eliminated. Then, the ball screw 53 is axially rotated (forward rotation) by the rotation of the prime mover 54 (servo motor) of the ball screw mechanism 5, and the ball screw nut 51 is raised (S5). As a result, as the bracket portion 52 fixed to the ball screw nut 51 rises, the upper springs 61a and 61b of the biasing means 6 are compressed, and the repulsive biasing force of the compressed upper springs 61a and 61b is applied to the upper facing member 441 ( It is attached to the driven shaft 31 via the moving part 4). As a result, it is possible to eliminate the difference of +3% or more between the measured value of the dynamic shaft load on the driven shaft 31 and the set value of the shaft load corresponding to each step of the operation pattern 1.

On the other hand, if the difference does not exceed +3% (S4: NO), it is determined that the difference is -3%, the measured value of the dynamic shaft load on the driven shaft 31 and the axis corresponding to each step of the operation pattern 1 are determined. In order to eliminate the difference from the set value of the load, the ball screw 53 is axially rotated (reverse rotation) by the rotation of the prime mover 54 (servo motor) of the ball screw mechanism 5, and the ball screw nut 51 is lowered (S6). As a result, as the bracket portion 52 fixed to the ball screw nut 51 descends, the lower springs 62a and 62b of the biasing means 6 are compressed, and the repulsive biasing force of the compressed lower springs 62a and 62b is reduced to the lower facing member 442 ( It is attached to the driven shaft 31 via the moving part 4). This makes it possible to eliminate a difference of -3% or more between the measured value of the dynamic shaft load on the driven shaft 31 and the set value of the shaft load corresponding to each step of the operation pattern 1.

That is, the arithmetic control unit 171 of the prime mover 54 is based on the difference between the measured value of the dynamic shaft load for the driven shaft 31 and the set value of the dynamic shaft load in the operation pattern and the step (order) input in advance. Feedback control that reflects the movement operation of the ball screw nut 51 by the rotation control is executed.

After the processing of S5 or S6, the processing shifts to the processing of S3 again. If the difference is within ±3 in the process of S3 (S3: YES), the ride-out measuring device 14 automatically measures the ride-out of the belt 10 (S7). The measurement of the rideout (RO) of the belt 10 is repeated until the predetermined number of cycles is reached (S8). Note that the number of cycles in this embodiment is two.

After the processing of S8, one step operation is completed and the next step operation is performed. For example, if the stage is currently Step 1, the operation proceeds to Step 2. Then, the arithmetic control unit 171 determines whether or not all step operations have been completed (S9). If all step operations have not been completed (S9: NO), the process returns to S2. On the other hand, when all the step operations have been completed (S9: YES), this operation flow ends. In the present embodiment, when the operation in step 10 is completed, it is determined that all step operations are completed.

Then, the data is output (S10). In the present embodiment, the measured value of the rideout (RO) of the belt 10 measured on the display unit 172 of the PC 17 is displayed.

(Ride-out measurement device 14 measures the ride-out of the belt 10)
The automatic measurement of the ride-out (RO) of the belt 10 by the ride-out measuring device 14, which is executed in the processes of S7 and S8, is performed by using the laser micrometer 141 provided through the heat-resistant glass forming the constant temperature bath 12. Perform using. As shown in FIG. 12, the position of the measurement object laser-scanned by the light emitter/receiver of the laser micrometer 141 in the belt width direction is approximately the center (reference point) of the outer peripheral surface of the drive pulley 2 and the back surface of the belt 10 (reference point). It was the central part of the outer peripheral surface). The ride-out measurement method is substantially the same as the disclosure content of Patent Document 1. Accordingly, the ride-out of the belt 10 can be measured in a non-contact manner, and the measurement when the atmospheric temperature is raised can be performed from outside the constant temperature bath 12. Even if the belt 10 is a double-cog type low-edge cog V-belt, the same automatic measurement can be performed.

(Operation of the urging means 6 accompanying the ride-out measurement of the belt 10)
Next, regarding the state of the upper spring 61a (upper spring 61b) and the lower spring 62a (lower spring 62b) as the urging means 6, which accompanies the automatic measurement of the rideout of the belt 10 by the above-described automatic operation of the belt measuring device 1. explain.

(Axial load 0N)
Before the belt 10 is attached to the drive pulley 2 and the driven pulley 3 of the belt measuring device 1 (axial load 0N: no load), the moving part weight (driven pulley 3, driven shaft 31, driven base 41, load cell 43, Due to the total weight of the members including the load base 42, the frame 44, the biasing means 6, etc., as shown in FIGS. It will be in a compressed state between and. On the other hand, the lower springs 62a and 62b have a free length, and do not contact the bracket portion 52 but contact only the lower facing member 442.

(Dynamic shaft load 300N)
Even when the measured value of the dynamic shaft load on the driven shaft 31 measured by the load cell 43 is 300 N, as shown in FIGS. 9(a) and 9(b), the upper springs 61a and 61b are connected to the upper facing member 441 and the bracket portion 52. It will be in a compressed state between and. On the other hand, the lower springs 62a and 62b have a free length, and do not contact the bracket portion 52 but contact only the lower facing member 442. Until the measured value of the dynamic shaft load on the driven shaft 31 measured by the load cell 43 reaches 700 N (corresponding to the moving part weight), the upper springs 61a and 61b are compressed between the upper facing member 441 and the bracket part 52. Then, the repulsive biasing force of the compressed upper springs 61a and 61b is applied to the driven shaft 31 via the upper facing member 441 (moving portion 4). On the other hand, the lower springs 62a and 62b remain in the free length until the measured value of the dynamic shaft load on the driven shaft 31 measured by the load cell 43 reaches 700 N (corresponding to the moving part weight).

(Dynamic shaft load 700N)
When the measured value of the dynamic shaft load on the driven shaft 31 measured by the load cell 43 is 700 N (equal to the weight of the moving part), the upper springs 61a and 61b are In the free length state, both ends of the upper springs 61a and 61b are in a state of being substantially in contact with the upper facing member 441 and the bracket portion 52. On the other hand, the lower springs 62a and 62b are also in a free length state, and both ends of the lower springs 62a and 62b are substantially in contact with the bracket 52 and the lower facing member 442.

(Dynamic shaft load 1000N)
When the measured value of the dynamic shaft load on the driven shaft 31 measured by the load cell 43 is 1000 N, the upper springs 61a and 61b have a free length and have an upper facing member, as shown in FIGS. It does not contact 441 but contacts only the bracket portion 52. On the other hand, the lower springs 62a and 62b are in a compressed state between the bracket portion 52 and the lower facing member 442. After the measured value of the dynamic shaft load on the driven shaft 31 measured by the load cell 43 exceeds 700 N (corresponding to the moving part weight), the upper springs 61a and 61b are in the free length state. On the other hand, the lower springs 62a and 62b are compressed between the bracket portion 52 and the lower facing member 442, and the repulsive biasing force of the compressed lower springs 62a and 62b is driven by the lower facing member 442 (moving portion 4). 31 is added.

(effect)
According to the above configuration, the biasing means 6 (the upper springs 61a and 61b and the lower springs 62a and 62b) that applies the repulsive biasing force to the driven operation of the moving unit 4 has a spring constant smaller than the spring constant of the belt 10 to be stretched. Therefore, the moving operation of the driven shaft 31 in the stretching direction can be a moving operation to which the repulsive urging force of the urging means 6 is added. Thereby, the moving distance of the ball screw nut 51 in the ball screw mechanism 5 can be made larger than the moving distance of the driven shaft 31 (moving portion 4).
Therefore, in the process of applying a predetermined dynamic axial load to the driven shaft 31 using the ball screw mechanism 5, the biasing means 6 is not provided at the connecting portion between the moving portion 4 and the ball screw mechanism 5 (moving portion 4 and The structure in which the ball screw mechanism 5 is directly connected: compared to the belt measuring device 200 described later), the moving distance of the driven shaft 31 (moving portion 4) is reduced with respect to the moving distance of the ball screw nut 51 in the ball screw mechanism 5. can do.
That is, even when the increase amount of the axial distance after applying the pre-tension to the belt 10 is relatively small, it becomes easy to finely control the moving distance (axial distance) of the driven shaft 31, resulting in the dynamic axial load. Fine control of the driven shaft 31 is facilitated, and the target dynamic shaft load is accurately applied to the driven shaft 31 without the load being removed by the moving operation of the driven shaft 31 or being excessively applied. be able to.
Further, it is possible to grasp the difference from the target dynamic axial load based on the numerically displayed measured value of the dynamic axial load. Accordingly, based on the above difference, the moving distance (inter-axis distance) of the driven shaft 31 by the ball screw mechanism 5 is finely adjusted or controlled so that the measured value of the dynamic shaft load is within the range of the target dynamic shaft load. Can fit in.

Moreover, according to the said structure, the repulsive urging|biasing force can be given to the movement operation|movement of the moving part 4 corresponding to the load load of a wider range by the reason 1)-3) shown below. As a result, in the process of applying a predetermined dynamic shaft load to the driven shaft using the ball screw mechanism 5, even if the amount of increase in the axial distance after applying the pretension to the belt 10 is relatively small, a wider range is achieved. It becomes possible to easily control the moving distance (inter-axis distance) of the driven shaft in correspondence with the applied load, and the target dynamic shaft load can be accurately applied to the driven shaft 31.

1) The upper springs 61a and 61b and the lower springs 62a and 62b sandwich the bracket portion 52, which is connected to the ball screw nut 51 of the ball screw mechanism 5, between the upper facing member 441 and the lower facing member 442 and extend in the stretching direction. Since they are arranged apart from each other, when (A) the dynamic axial load is less than the moving part weight (the total weight of the part suspended by the belt 10), at least the stretching direction of the belt 10 (hereinafter, simply, The upper springs 61a and 61b on the loose side (referred to as the tension direction) are compressed and deformed to support the weight of the moving portion and give a repulsive biasing force to the moving operation of the moving portion 4. (B) When the dynamic shaft load exceeds the weight of the moving portion, at least the lower springs 62a and 62b on the tension side in the stretching direction are compressed and deformed, and a repulsive biasing force can be applied to the moving operation of the moving portion 4. ..
On the other hand, when the urging means 6 is not arranged between the upper facing member 441 and the lower facing member 442, the bracket portion 52 connected to the ball screw nut 51 of the ball screw mechanism 5 is sandwiched between them and is not separated from each other in the stretching direction (stretching). The effect that the target dynamic shaft load can be accurately applied to the driven shaft 31 in either one of the suspension directions is that the biasing means 6 is provided only on the loose side in the stretching direction with respect to the bracket portion 52. If the urging means 6 is disposed only on the tension side in the tension direction with respect to the bracket portion 52, the dynamic shaft load range is equal to or less than the moving portion weight. It is limited to the load range.

2) Both ends of the upper springs 61a and 61b and the lower springs 62a and 62b are not in a free state, and both ends of the upper springs 61a and 61b and the lower springs 62a and 62b are the bracket portions 52 (both surfaces in the stretching direction) and/ Alternatively, when it is fixed to the upper facing member 441 and the lower facing member 442, when one biasing means 6 in the stretching direction is compressed and deformed to apply a repulsive biasing force to the movement of the driven shaft 31, the stretching direction is increased. Since tensile stress is applied to the other urging means 6 and an urging force is applied in the moving direction of the driven shaft 31, the repulsive urging force to be applied to the moving operation of the driven shaft 31 is weakened. Therefore, when both ends of the upper springs 61a and 61b and the lower springs 62a and 62b are in a free state, more reliably than when both ends of the upper springs 61a and 61b and the lower springs 62a and 62b are not in a free state. The repulsive biasing force can be applied to the moving operation of the moving unit 4.

3) When the upper springs 61a and 61b and the lower springs 62a and 62b are set to the free length (the urging state in which the repulsive urging force does not reach the moving operation of the moving portion 4), the measured value of the dynamic shaft load is moved. When the arithmetic control is performed so as to be equal to the weight of the moving portion, the weight of the moving portion (weight on the spring, so to speak, tare, so to speak) can be reliably applied, as in a known counterbalance mechanism (for example, Japanese Unexamined Patent Publication No. 2002-257501) in a dead weight type measuring machine. It has the effect of being able to reset the zero point of weight). This allows the range of dynamic axial loads to start from zero.

According to the above configuration, the guide shaft 443a fixed between the upper facing member 441 and the lower facing member 442 inside the coil winding of the upper springs 61a and 61b and the lower springs 62a and 62b of the biasing means 6. Since the configuration is such that the 443b is passed through, it is possible to simply realize a device configuration in which the upper springs 61a and 61b and the lower springs 62a and 62b do not fall out.

Further, according to the above configuration, both ends of the upper springs 61a and 61b and the lower springs 62a and 62 are substantially in contact with the bracket portion 52 and the upper facing member 441 and the lower facing member 442 when they have a free length. .. Therefore, from the state where the repulsive urging force of the upper springs 61a and 61b and the lower springs 62a and 62b does not reach the moving operation of the moving section 4, the repulsive urging force of the upper springs 61a and 61b and the lower springs 62a and 62b changes to the moving section 4. It is possible to make a transition to a state that extends to the movement operation of the above without any interruption. That is, the movement operation of the driven shaft 31 (moving portion 4) using the ball screw mechanism 5 can be operated with almost no interruption and continuity.

According to the above configuration, in the process of applying the predetermined dynamic shaft load to the driven shaft 31 using the ball screw mechanism 5, the increase in the inter-axial distance after applying the pre-tension to the belt 10 is relatively small. However, the movement distance (inter-axis distance) of the driven shaft 31 is finely controlled by an automatic operation so that it is within the range of the target dynamic shaft load, and the target dynamic shaft load is accurately applied to the driven shaft. be able to.
Furthermore, by setting and registering multiple operation patterns and steps (order) consisting of a combination of dynamic shaft load and other conditions (driving pulley rotation speed, ambient temperature) as an operation program in advance, the operation can be performed by one operation. Even if you perform automatic operation that continuously changes the dynamic axial load in multiple stages (from small load to large load), you can measure changes in the dimensions of each part such as the rideout of the belt between each step without any problems. It can be connected to the evaluation of the belt characteristics such as the lateral rigidity of 10.

The ride-out of the belt 10 using the belt measuring device 1 (example) was measured, the verification with the conventional belt measuring device 200 (comparative example) was performed, and the load accuracy of the belt measuring device 1 was evaluated.

The belt 10 used in the following examples and comparative examples is a low edge cog type V belt described above, and is a speed change belt having the specifications shown in Table 2.

A twisted rope of polyester cord is used for the core wire 103. BOC is the outer peripheral length of the belt 10.

The spring constant of the belt 10 used in Examples and Comparative Examples was measured by the following method.
(1) The outer peripheral side and the inner peripheral side of the belt 10 were turned over to make the inner peripheral surface a flat surface (reinforcing cloth 104).
(2) Using an autograph, a pair of tubular jigs having a flat outer peripheral surface are brought into contact with the inner peripheral surface of the belt 10, and in a mode in which they face each other while being separated from each other in the belt longitudinal direction, the tensile mode is set. Then, a test (tensile test) was carried out in which the tubular jig was separated at a predetermined speed to give the belt 10 a strong elongation.
(3) As a result, a graph relating to the load (N) applied to the belt 10 and the elongation (%) of the belt 10 per belt length, that is, a so-called S-S curve of the belt (Strain-Pressure Curve) (not shown) ) Got.
(4) The spring constant of the belt 10 used in the examples and the comparative examples is about 200 N/mm from the inclination of the straight line portion of this graph (the load is about 1600 N at 1% elongation of the belt per belt length). Met.

(Measurement result of ride-out of belt 10 by automatic driving)
The rideout of the belt 10 was measured by the automatic operation of the belt measuring device 1. The measurement results of the ride-out of the belt 10 are shown in Table 3.

(Major movement distance when applying dynamic axial load)
With respect to the belt measuring device 1 (example) according to the present embodiment and the conventional belt measuring device 200 (comparative example), the main part moving distance at the time of applying a dynamic axial load is measured and compared.

As shown in FIG. 13, the conventional belt measuring device 200 (comparative example) is a ball screw type in which the biasing means 6 is not provided at the connecting portion between the moving portion 4 and the ball screw mechanism 5. That is, the belt measuring device 1 according to the example includes the biasing means 6, but the belt measuring device 200 according to the comparative example does not include the biasing means 6. The belt measuring device 200 is the same as the belt measuring device 1 according to the embodiment except that the biasing means 6 is not provided.

Specifically, the bracket portion 52 fixed to the ball screw nut 51 of the ball screw mechanism 5 is directly fixed to the frame 44 (see the hatched portion in FIG. 13). In the belt measuring device 200 according to the comparative example, the weight of the moving part 4 is supported by the ball screw nut 51, and the moving part 4 is not suspended. Therefore, the zero point of the moving part weight required for the belt measuring device 1 according to the embodiment is zero. No reset operation is necessary.

Tables 4 and 5 show the main part moving distances when the dynamic axial loads of 300 N and 1000 N are applied to the belt measuring device 1 according to the present embodiment (example) and the conventional belt measuring device 200 (comparative example). Show. Specifically, the moving distance (a) of the ball screw nut 51 of the ball screw mechanism 5 and the moving distance (b) of the driven shaft 31 (moving portion 4) were compared.

Here, the moving distance (a) of the ball screw nut 51 and the moving distance (b) of the driven shaft 31 (moving portion 4) are both at the time of applying pre-tension (200 N in both the example and the comparative example) to the belt. Was set as the starting point (zero moving distance). The moving distance (b) of the driven shaft 31 (moving portion 4) is equal to the change amount (increase amount ΔL) of the inter-axis distance because the main shaft 21 is the fixed shaft. Note that the value of the moving distance (b) of the driven shaft 31 (moving portion 4) depends on the amount of extension of the belt 10 after the belt 10 is pretensioned and the value after the belt 10 is pretensioned. It is a value including the change amount (increase amount ΔL) of the inter-axis distance due to the change of the rideout (the position of the back surface of the belt 10).

(Movement distance (mm) of each part when a dynamic axial load of 300N is applied)

(Movement distance (mm) of each part when a dynamic axial load of 1000 N is applied)

(Comparative example)
In the case of the belt measuring device 200 according to the comparative example, the moving distance (a) of the ball screw nut 51 was equal to the moving distance (b) of the driven shaft 31 (moving portion 4). This is because the biasing means 6 is not provided between the moving portion 4 and the ball screw mechanism 5.

(Example)
On the other hand, in the case of the belt measuring device 1 according to the embodiment, the moving distance (a) of the ball screw nut 51 is significantly larger than the moving distance (b) of the driven shaft 31 (moving portion 4) (dynamic shaft load). Approximately 7 times when 300N is applied and approximately 3 times when dynamic axial load of 1000N is applied). This is because the urging means 6 having a spring constant smaller than the spring constant (about 200 N/mm) of the belt 10 to be stretched at the connecting portion between the moving portion 4 and the ball screw mechanism 5 (when a dynamic axial load of 300 N is applied). Since the upper springs 61a and 61b that act are 98 N/mm, and the lower springs 62a and 62b that act when a dynamic axial load of 1000 N is applied are approximately 105 N/mm, the moving distance of the ball screw nut 51 (a ) Can be made larger than the moving distance (b) of the driven shaft 31 (moving portion 4). In other words, it means that the movement operation of the driven shaft 31 can be the urging movement in which the repulsion urging force is added to the movement operation of the moving portion 4.

Note that the effect of significantly increasing the moving distance (a) of the ball screw nut 51 than the moving distance (b) of the driven shaft 31 (moving portion 4) is lower in the medium load area (300 N) in the low load area (300 N). It was larger than the case of 1000 N). This is because under the same target belt 10, the smaller the applied load (F) is, the smaller the variation (increase ΔL) in the axial distance after the pretension is applied to the belt 10. It is considered that this factor and the factor relating to the setting of the repulsive urging force by the urging means 6 appear together. That is, the latter factor is structurally related, and specifically, depends on the setting of the spring constant (including the number of parallel arrangements) of the biasing means 6 (the upper springs 61a and 61b, the lower springs 62a and 62b). It is believed that there is.

(Load accuracy evaluation test)
Next, as the evaluation of the load accuracy, the difference (%) between the displayed value of the axial load and the test value is compared and evaluated between the belt measuring device 1 according to the example and the belt measuring device 200 according to the comparative example. did.

As an evaluation item, the difference (%) between the displayed value of the axial load and the test value was used as the index of load accuracy. The smaller the load accuracy value, the more preferable.

As the evaluation method, (1) the drive pulley 2 and the driven pulley 3 in the belt measuring device 1 according to the example and the belt measuring device 200 according to the comparative example are removed and connected between the main shaft 21 and the driven shaft 31. Connect the test load cell directly through the tool. In the belt measuring device 1 of the embodiment, the removed driven pulley 3 is attached to an arbitrary part of the moving part 4. (2) The permissible shaft of the belt measuring device 1 according to the example and the belt measuring device 200 according to the comparative example at the moving speed of the driven shaft 31 to the pulling side (downward) of about 0.15 mm/sec in the manual operation. The load range (200N to 3000N) is moved from near the lower limit to near the upper limit. (3) In the belt measuring device 1 of the embodiment, while the driven shaft 31 is moving, the driven shaft 31 is sequentially and arbitrarily stopped for reading the axial load and detected by the load cell 43 in the belt measuring device 1 of the embodiment. The display value of the axial load (the static axial load, not the dynamic in this test because there is no belt running in this test) and the verified value of the axial load detected by the verification load cell are read at the same time, and the displayed value and the verified value of the axial load are read. The difference (%) level was measured. Similarly, in the belt measuring device 200 of the comparative example, during the movement of the driven shaft 31, the load cell 43 in the belt measuring device 200 of the comparative example detects the axial load by temporarily temporarily stopping the reading. The displayed value of the axial load and the verified value of the axial load detected by the test load cell were read at the same time, and the level of the difference (%) between the displayed value of the axial load and the verified value was measured. Then, the level (%) of the difference between the axial load display value and the verification value of the belt measuring device 1 (with the biasing means 6) according to the example, and the belt measuring device 200 (biasing means) according to the comparative example. Comparative evaluation was carried out with the level (%) of the difference between the displayed value of the axial load (no 6) and the test value. The level of difference (%) between the axial load display value and the test value in the example and the level (%) difference between the axial load display value and the test value in the comparative example are shown in the graph of FIG.

As an evaluation standard (target), (1) the difference between the displayed value of the axial load and the test value (load accuracy) is within 3% (absolute evaluation). In addition, (2) the level (%) of the difference between the display value and the verification value of the axial load of the belt measuring device 1 according to the example is the same as the display value of the axial load of the belt measuring device 200 according to the comparative example. Significantly smaller than the level of difference (%) from the value (relative evaluation). If these two evaluations are satisfied, the evaluation of the load accuracy is high (◯).

(Absolute evaluation)
As shown in FIG. 14, in both the belt measuring device 1 of the example and the belt measuring device 200 of the comparative example, the difference (load accuracy) between the display value and the verification value of the axial load is within 3%, and I am satisfied with the goal as an objective evaluation. The average value of the difference (load accuracy) (%) between the displayed value of the axial load and the test value was 0.49% in the belt measuring device 1 of the example, and 1.9 in the belt measuring device 200 of the comparative example. It was 22%.

(Relative evaluation)
As shown in FIG. 14, in the belt measuring device 1 of the example, compared with the belt measuring device 200 of the comparative example, the level of the difference (load accuracy) between the displayed value of the axial load and the verification value (load accuracy) is It is also small on the horizontal axis), which shows that it is preferable. That is, it can be said that the belt measuring device 1 of the example has a high evaluation of load accuracy (◯). Generally, the belt measuring device 1 of the embodiment is about 1/2.5 of the average value in comparison with the comparative example, about 1/3 in the low load region of about 300 N, and about the same in the medium/high load region of 1000 N or more. It became 1/2. This has the ball screw mechanism 5 by providing the biasing means 6 at the connecting portion between the moving portion 4 and the ball screw mechanism 5, but does not have the biasing means 6 at the connecting portion between the moving portion 4 and the ball screw mechanism 5. It is considered that this indicates that the load can be finely controlled with an accuracy of about 2.5 times (3 times in the low load area and about 2 times in the medium/high load area) on average, as compared with the configuration. ..

(Consideration on load accuracy from the ball screw mechanism 5)
For example, the moving distance (a) of the ball screw nut 51 of 14.3 mm when the dynamic axial load of 1000 N is applied in the examples shown in Table 5 is 9.8 mm (spring contraction amount) and 4.5 mm (described in Table 3). Amount of change in inter-axis distance: sum of belt ride-out change amount and belt extension amount).・The spring constant of the belt 10 is approximately 200 N/mm. ・The spring constant of the lower springs 62a and 62b is approximately 105 N/mm (when two parallels are arranged).

In order to realize the load accuracy of 1000 N±3% (30 N) in the belt measuring device 200 of the comparative example, the relationship of the following equation is required.
{(30/200)/6}×20×360=180 (Equation 1)
Here, 30 is a load accuracy range, 200 is a spring constant of the belt 10, 6: is a lead of the ball screw 53, and 20 is a reduction ratio of the speed reducer 55. From this, it can be said that, in order to realize the load accuracy of 1000 N±3% (30 N) in the belt measuring device 200 of the comparative example, it is necessary to control the servo motor of the prime mover 54 within ±180°.

Therefore, when the embodiment of this configuration is used, the following equation is obtained.
{(30/63)/6}×20×360=571.4 (Equation 2)
Here, 30: load accuracy range, 63: spring constant of compound system of belt 10 and compression spring (200×(4.5/14.3)=63), 6: lead of ball screw 53, 20: reducer The reduction ratio is 55. From this, it can be said that the servomotor of the prime mover 54 can be controlled within ±571.4°, and the load accuracy can be realized about 3 times easier (Equation 2/Equation 1).

From the above, it can be considered that the belt measuring apparatus 1 according to the embodiment can theoretically finely control the load with the accuracy of about three times with the same servo motor, so that the above-described load accuracy evaluation is performed. It can support the evaluation result of the test.

(Other embodiments)
The present invention is not limited to the above-described embodiments and examples, and various design changes are possible within the scope of the claims.

For example, the belt measuring device 1 is not limited to the vertical type, and may be the horizontal type. In this case, the belt 10 is wound around the drive pulley 2 and the driven pulley 3 arranged in the horizontal direction, and the driven shaft 31 is moved in the horizontal direction by the rotation of the ball screw 53 arranged in the horizontal direction. ..

Further, the dimensions of each part of the belt 10 that can be measured using the belt measuring device 1 are not limited to ride-out, and, for example, the circumferential length, width, thickness, warpage, meandering amount of the belt 10, and further the toothed belt. Tooth pitch, etc. are included.

The biasing means 6 is not limited to a configuration in which two springs are arranged in parallel like the above-mentioned upper springs 61a and 61b and lower springs 62a and 62b. For example, even if only one spring is arranged, three biasing means are arranged in parallel. The above arrangement may be adopted.

Further, in the urging means 6, the upper spring 61a (upper spring 61b) and the lower spring 62a (lower spring 62b) are attached to the ball screw nut 51 of the ball screw mechanism 5 between the upper facing member 441 and the lower facing member 442. The configuration is not limited to the configuration in which the fixed bracket portion 52 is sandwiched and is separated from each other in the stretching direction (vertical direction). For example, the configuration is limited to one of the belt stretching directions. May be Specifically, the upper spring 61a (upper spring 61b) as the biasing means 6 may be arranged only between the upper facing member 441 and the bracket portion 52, or the biasing means 6 may be used. The lower spring 62a (lower spring 62b) may be arranged only between the bracket portion 52 and the lower facing member 442.

Further, both ends of the upper spring 61a (upper spring 61b) and the lower spring 62a (lower spring 62b) as the urging means 6 do not have to be in a free state, and either one end Only one may be free.

Further, the urging means 6 is not limited to the coil spring described above, and has, for example, a configuration like an arc-shaped leaf spring (upper leaf springs 301a and 301b and lower leaf springs 302a and 302b) as shown in FIG. May be.

Further, the servo motor in the ball screw mechanism 5 has a difference between the measured value of the dynamic shaft load on the driven shaft 31 detected by the load cell 43 and the preset value of the dynamic shaft load in the operation pattern and step (order) input in advance. It is not limited to feedback control based on, for example, the difference between the measured value of the dynamic shaft load on the driven shaft 31 and the preset value of the dynamic shaft load in the operation pattern and step (order) input in advance. Based on the above, rotation operations such as rotation ON, rotation OFF, and rotation direction may be manually performed.

1 belt measuring device 2 drive pulley 21 main shaft 3 driven pulley 31 driven shaft 4 moving part 43 load cell 5 ball screw mechanism 51 ball screw nut 52 bracket part 53 ball screw 54 prime mover 55 reducer 6 biasing means 61a, 61b upper spring 62a, 62b lower Spring 10 Belt 14 Ride-out measuring device 17 PC
171 Operation control unit 172 Display unit

Claims (5)

A belt is wound around a drive pulley provided on the main shaft and a driven pulley provided on the driven shaft, and the driven shaft is moved in the belt tension direction to apply a predetermined dynamic shaft load to the driven shaft. A belt measuring device for measuring the dimensions of each part of the belt that has been run in the state of
A moving part provided on the driven shaft,
A ball screw mechanism for moving the moving portion in the stretching direction of the belt according to the movement of the ball screw nut screwed to the ball screw;
Urging means provided at the connecting portion between the moving portion and the ball screw mechanism, having a spring constant smaller than the spring constant of the belt, and applying a repulsive urging force to the driven operation of the moving portion,
A load cell that is provided in the moving unit and detects a dynamic shaft load with respect to the driven shaft,
Based on an electric signal from the load cell, a calculation control unit that calculates a measured value of the dynamic shaft load with respect to the driven shaft,
A belt measuring device, comprising: a display unit for numerically displaying the measured value of the dynamic shaft load with respect to the driven shaft, which is calculated by the calculation control unit. The moving member has a pair of opposing members that receive the repulsive biasing force of the biasing means,
The urging means has a first urging means and a second urging means,
The first urging means and the second urging means are arranged between the pair of opposing members with a bracket portion fixed to a ball screw nut of the ball screw mechanism being sandwiched between them so as to be separated from each other in the tension direction. Further, both ends of the first urging means and the second urging means are arranged in a free state,
The arithmetic control unit equalizes the measured value of the dynamic shaft load with respect to the driven shaft to the weight of the moving unit when the first urging unit and the second urging unit are set in a free length state. The belt measuring device according to claim 1, wherein the belt measuring device is configured to perform arithmetic control. The first biasing means and the second biasing means are coil springs,
A guide shaft is fixed between the pair of opposing members,
3. The belt measuring instrument according to claim 2, wherein the coil spring of the first urging means and the coil spring of the second urging means are inserted into the guide shaft with the bracket portion interposed therebetween. apparatus. The first urging means and the second urging means are characterized in that both ends thereof are substantially in contact with the bracket portion and the facing portion when they are in a free length. The belt measuring device described. The ball screw mechanism has a prime mover that controls the movement of the ball screw nut screwed to the ball screw,
The arithmetic control unit, based on the difference between the measured value of the dynamic shaft load and the preset value of the dynamic shaft load input in advance, for the movement operation of the ball screw nut screwed to the ball screw by the prime mover. The belt measuring device according to any one of claims 1 to 4, characterized in that a feedback control is executed.