JP4114935B2 - measuring device - Google Patents

Description

The present invention relates to a measuring device that measures the degree of wear of an actuated part .

Some of such measuring devices include a mechanism that converts rotational motion into reciprocating linear motion, and this mechanism includes a cam provided on a rotating shaft of a motor and a contact that elastically contacts the cam with a spring. Part. In such a configuration, when the cam is rotated at a high speed, jumping occurs at the contact portion. In addition to not being able to obtain accurate linear motion, it generates vibration and noise.

  Therefore, in order to eliminate such obstacles, for example, a technique disclosed in Patent Document 1 below has been proposed as a conventional technique. This is a conjugate cam device in which the cam follower receives an action from the plate cam during both forward and backward movements of the linear motion. The configuration is such that the rotating drive shaft is provided with a forward plate cam and a reverse plate cam, the swinging forward lever is provided with a cam follower that contacts the forward plate cam, and the swinging reverse lever is reversely driven. A cam follower that is in contact with the plate cam is provided, and a driven portion made of a roller is provided at the tip of the forward lever and the reverse lever. The forward driven portion is engaged with the forward block of the linear moving body, and the backward driven portion is engaged with the backward block of the linear moving body. In this way, the cam followers of the forward lever and the reverse lever are always brought into contact with the plate cam, and the linear moving body is reciprocated so as not to cause jumping.

Moreover, what is shown by the following patent document 2 is proposed as a prior art. This is to remove the influence of vibration particularly when the cam mechanism is speeded up. A cam follower is fitted into a cam groove of a cam rotated by a motor to convert the rotational motion into a linear motion. The cam curve of the cam groove is formed in a shape that does not generate vibration.
JP-A-9-310743 (paragraph [0006], paragraph [0019] to paragraph [0023]) JP 2001-317612 A (paragraph [0006], paragraph [00109], paragraph [0016] to paragraph [0020])

  However, in the prior art disclosed in Patent Document 1, a forward lever and a reverse lever are prepared, and a driven portion made of a roller is provided at each tip. Since the forward driven portion is engaged with the forward block of the linear moving body and the backward driven portion is engaged with the backward block of the linear moving body, it is not suitable for operating at high speed. . That is, at high speeds, there is a problem in that the rotational motion cannot be smoothly converted into a linear reciprocating motion due to an increase in frictional resistance caused by the roller in the forward block and the reverse block, and the occurrence of vibration.

  On the other hand, in the prior art disclosed in Patent Document 2, vibration can be prevented during high-speed operation, but it is necessary to select and replenish a lubricant for reducing the frictional resistance between the cam groove and the cam follower. . Moreover, not only is it troublesome to set the cam curve of the cam groove to prevent the occurrence of vibration, but also because the cam curve corresponds to a specific vibration component, the speed can be increased over a wide range by a common mechanism. There was a problem that it was impossible to change and use.

Accordingly, the present invention aims to provide a measuring device for measuring the degree of the conventional problems were removed, in particular high-speed reciprocating motion suitable rotary motion is converted into linear reciprocation of the driven portion abrasion To do.

In order to solve the above-mentioned problem, the measuring device of the invention according to claim 1
A rotating shaft rotated by a drive motor ;
A first eccentric cam attached to the rotating shaft;
A second eccentric cam attached to the rotating shaft in a positional relationship opposite to the first eccentric cam;
A first abutting portion arranged in contact with the outer peripheral surface of the first eccentric cam and coupled to the actuated portion;
Wherein relative to the first eccentric cam disposed in contact with the outer peripheral surface of the second eccentric cam at a position facing each other across the rotary shaft, the equal correct weight on the weight of said first contact portion Two abutting portions;
The first abutting portion has a plane parallel to the axis of the rotating shaft, and has one end as a fixed end and the other end as a free end, and the first abutting portion is directed to the first cam. First pressing means formed from a leaf spring having elastic force to press;
The second abutting portion has a plane parallel to the axis of the rotating shaft, the one end is a fixed end and the other end is a free end, and the second abutting portion is attached to the first abutting portion. The second facing the displacement direction
Second pressing means formed from a leaf spring that presses in the direction of the cam with an elastic force equal to the elastic force of the first pressing means and every driving instant ;
E Bei a support spring having a stiffness hemisphere tip, and a frictional force sensor unit base side is attached to the supporting spring, and a measuring unit for measuring the degree of wear of the driven portion,
One end of the rotary shaft is connected on the same axis of the drive motor, and the rotary shaft is rotated by the drive motor,
Arranging the first eccentric cam and the second eccentric cam in order from the driving force side of the rotary shaft in the axial direction;
The rigid hemisphere is pressed against and brought into contact with the actuated portion by the elastic force of the support spring,
The actuated part is worn on the surface by repeating the linear reciprocation of the first abutting part in a state where the rigid hemisphere is abutted,
The frictional force sensor unit measures a frictional force that changes as the worn state of the operated part progresses .

In the measuring apparatus according to the second aspect of the present invention, the first pressing means and the second pressing means are formed of a set of leaf springs arranged at a predetermined interval via a spacer. It is characterized by being.

The measurement apparatus of the invention according to claim 3, wherein the first eccentric cam and the second eccentric cams, circular rotated via a circular central portion, the circular center portion concentrically with lubrication And an outer peripheral portion, wherein the rotary shaft is penetrated and fixed at a position eccentric from a center position of the circular central portion.

This invention exhibits the following effects by adopting the above-described configuration. According to the measuring apparatus of the first aspect of the present invention, the first abutting portion and the second abutting portion are respectively provided for the first cam and the second cam that are located at different positions facing the rotation axis. The first pressing means and the first pressing means that abut against each other from opposite directions, the first abutting portion side and the second abutting portion side are equal in weight, and generate equal pressing force at every driving moment . Since the pressing is performed by the second pressing means, the movement of the center of gravity of the first contact portion including the operated portion and the entire second contact portion does not substantially occur. Therefore, no vibration is generated regardless of the period of operation. Further, since the leaf springs forming the first pressing means and the second pressing means are arranged with a plane parallel to the axis of the rotation shaft, the first contact portion and the second contact portion rotate. There is no displacement in the axial direction relative to the axis. Therefore, the first contact portion and the second contact portion do not vibrate in the axial direction. That is, the device itself does not vibrate, and the actuated portion coupled to the first contact portion is displaced only in the direction displaced by the eccentricity of the first cam. A displacement operation can be performed. The effect is particularly remarkable for a device that reciprocates at a high cycle.

According to the measuring device of the invention of claim 2 , since the first pressing means and the second pressing means in claim 1 are formed by a pair of leaf springs, the first pressing means with a large elastic force. Can be pressed against the first cam and the second contact portion against the second cam. Therefore, the reciprocating motion can be obtained with high accuracy without causing jumping. Further, since the leaf spring is not displaced at all with respect to the axial direction of the rotating shaft, the actuated portion coupled to the first abutting portion vibrates only in the direction displaced by the eccentricity of the first cam. Thus, a stable displacement operation can be performed without being affected at all. Further, the first contact portion, the second contact portion, and the operated portion do not require a guide mechanism for reciprocal direct motion. Therefore, not only the configuration is simple, but also a stable operating state can be obtained without being affected at all by the frictional resistance generated by the guide mechanism.

Further, according to the measuring apparatus of the invention according to claim 3, claim 1 and a first eccentric cam and the second eccentric cams of claim 2, the first contact portion or the second contact portion Since the circular outer peripheral portion with which the abuts is provided in the circular central portion through the lubrication portion and is formed by penetrating and fixing the rotary shaft at a position eccentric from the central position of the circular central portion, the second is determined from the rotational force of the rotary shaft. The frictional resistance in the conversion of the abutment portion into the reciprocating linear motion is extremely small, and an efficient conversion can be performed. In addition, since all are configured using circular members, a highly accurate apparatus can be formed relatively easily.

The best mode for carrying out the present invention is an embodiment described below.

An embodiment of the present invention will be described with reference to FIGS. 1 is a perspective view of a measuring apparatus according to an embodiment of the present invention, FIG. 2 is an enlarged plan view showing an eccentric cam portion in FIG. 1, FIG. 3 is a plan view of the measuring apparatus according to an embodiment of the present invention, and FIG. It is a side view of the measuring apparatus in the Example of this invention.

  In the figure, a motor 2 that is a driving source of rotational force is disposed on a base 1. A first eccentric cam 4 and a second eccentric cam 5 are attached to the rotating shaft 3 of the motor 2. The first contact portion 6 is in contact with the outer peripheral surface of the first eccentric cam 4, and the second contact portion 7 is in contact with the outer peripheral surface of the second eccentric cam 5. In position. The first contact portion 6 is positioned by being attached to a free end of a leaf spring 81 that forms a first pressing portion 8 provided on the base 1. Similarly, the second contact portion 7 is positioned by being attached to a free end of a leaf spring 91 that forms a second pressing portion 9 provided on the base 1. The actuated portion 10 is coupled to the first contact portion 6.

  The first eccentric cam 4 and the second eccentric cam 5 have the same configuration, and as shown in detail in FIG. 2, the circular central portions 41 and 51 and the lubricating portions 42 concentrically with the circular central portions 41 and 51, respectively. , 52 and circular outer peripheries 43 and 53 rotating through the same. The lubrication parts 42 and 52 are made of ball bearings, oilless metal, or the like. Through holes 44 and 54 are formed in the circular central portions 41 and 51 at positions eccentric from the center position P. The first eccentric cam 4 and the second eccentric cam 5 are fixed through the rotating shaft 3 in the through holes 44 and 54, respectively, but are attached with a positional relationship of 180 degrees relative to each other. ing.

  The first pressing portion 8 forms a first pressing means, and two leaf springs 81 are assembled in parallel to one end and the other end thereof via a space 82, and one end is a fixed base. 1 is fixed to a fixing portion 11 provided in the base plate 1. And the 1st contact part 6 attached to the other end which is a free end is pressed to the direction of the 1st eccentric cam 4 with the elastic force of the leaf | plate spring 81. FIG. The second pressing portion 9 forms a second pressing means. Two leaf springs 91 are assembled in parallel at one end and the other end via a space 92 and one end is a fixed end. It is fixed to the fixing part 11. Then, the second abutting portion 7 attached to the other end, which is the free end, has a pressing force equal to the pressing force in the first pressing portion 8 in the direction of the second eccentric cam 5 by the elastic force of the leaf spring 91. It comes to be pressed.

  In the figure, the first eccentric cam 4 and the second eccentric cam 5 are in the actuated rotational positions where the first abutting portion 6 and the second abutting portion 7 are in the most separated state. Is shown. On the other hand, although not shown, when the driving of the motor 2 is stopped, the first eccentric cam 4 and the second eccentric cam 5 are pressed by the first pressing portion 8 and the second pressing portion 9. Thus, the first abutting portion 6 and the second abutting portion 7 are stabilized in a state of being closest to each other by rotating an angle of 90 degrees.

  An actuated part 10 is fixedly connected to the first contact part 6. The actuated part 10 is a flat test material having a relatively small mass and is fixed by a screw 12. Yes. The actuated portion 10 reciprocates by the first pressing portion 6 that contacts the rotating first eccentric cam 4. The reciprocating motion of the actuated portion 10 is substantially linear because the length of the leaf spring 81 is sufficiently large with respect to the stroke.

  Reference numeral 13 denotes a measurement unit for measuring the degree of wear of the test member, and is supported by a support unit 14 provided on the base 1. The measurement unit 13 includes a support spring 132 having a rigid hemisphere 131 at the tip via a gimbal spring, and a frictional force sensor unit 133 to which the base side of the support spring 132 is attached. The rigid hemisphere 131 is pressed against and brought into contact with the test member by the elastic force of the supporting spring 132. The surface of the test member is worn due to repeated linear reciprocation of the first contact portion 6 in a state where the rigid hemisphere 131 is in contact. The frictional force that changes as the wear state progresses is measured by the frictional force sensor 133.

Next, the operation of the above-described configuration of the embodiment of the present invention will be described. First, a setting for measuring the degree of wear of the test member is performed. In this case, the actuated part 10, which is a test member, is fixed on the first abutting part 6 with screws 12. Then, the rigid hemisphere 131 is pressed onto the test member with a predetermined pressure by the support spring 132.

  Thereafter, the motor 2 is operated to rotate the first eccentric cam 4 and the second eccentric cam 5 attached to the rotary shaft 3 at high speed. The first contact portion 6 and the second contact portion 7 reciprocate at high speed. Therefore, the actuated part 10 that is a test member reciprocates linearly at high speed, and the surface thereof is worn by the rigid hemisphere 131. The degree of wear that changes over time can be measured by the frictional force sensor 133.

  In the state where the rotational motion is converted into the reciprocating motion, the influence of the movement of the center of gravity on the first eccentric cam 4 side including the first contact portion 6, the spacer 82, the differential portion 10, and the like viewed from the rotational shaft 3. Is canceled by the movement of the center of gravity on the second eccentric cam 5 side composed of the second contact portion 7 and the spacer 92 or the like. That is, since the first eccentric cam 4 and the second eccentric cam 5 are attached to the rotating shaft 3 with a positional relationship different from each other by 180 degrees, the load caused by each rotation does not vary as viewed from the rotating shaft 3. Therefore, no vibration is generated in the base 1, the rotating shaft 3, and the like.

  The first pressing portion 8 is arranged in parallel with the axis of the rotary shaft 3 and in parallel with the spacer 82, and the two leaf springs 81 are deformed into an S shape so as to generate a pressing force. The first contact portion 6 located at the tip performs a reciprocating motion substantially linearly. On the other hand, the second pressing portion 9 has the same configuration as that of the first pressing portion 8. Therefore, the second contact portion 7 linearly reciprocates similarly to the first contact portion 6.

  Further, the leaf spring 81 is not displaced with respect to the direction of the central axis of the rotary shaft 3. Therefore, the first contact portion 6 moves only in the direction displaced by the eccentricity of the first eccentric cam 4. The leaf spring 91 has the same configuration as the leaf spring 81. Therefore, the second contact portion 7 moves only in the direction displaced by the eccentricity of the second eccentric cam 5.

  In the first eccentric cam 4, the circular outer peripheral portion 43 is freely rotated by the lubricating portion 42 with respect to the circular central portion 41. Therefore, even if the circular outer peripheral portion 43 is stationary by the contact of the first contact portion 6, it does not become a load with respect to the rotation of the rotating shaft 3. Therefore, the rotational torque of the motor 2 is efficiently converted into a linear reciprocating motion. Since the second eccentric cam 5 has the same configuration as that of the first eccentric cam 4, no load is applied to the rotary shaft 3 in the same manner.

  The mechanism for converting the rotational motion of the above-described embodiment into the reciprocating motion is divided into a first eccentric cam 4 and a second eccentric cam 5 having different mounting positions at an angle of 180 degrees with respect to the rotational shaft 3. The first abutting portion 6 and the second abutting portion 7 are in contact with each other from the opposite directions. The first abutting portion 6 is pressed against the first eccentric cam 4 by the first pressing portion 8, and the second abutting portion 7 has a second pressing force equal to the pressing force of the first pressing portion. Is pressed against the second eccentric cam 5. Furthermore, the weights of the first contact portion 5 side and the second contact portion 6 side are substantially equal. Accordingly, the movements of the centers of gravity of each other are canceled out, and the load does not fluctuate as viewed from the rotating shaft 3, so that no vibration occurs in the base 1, the rotating shaft 3, and the like.

  Further, since the surfaces of the leaf springs 81 and 91 forming the first pressing portion 8 and the second pressing portion 9 are arranged parallel to the central axis of the rotating shaft 3, The second contact portion 7 is not displaced in the direction of the central axis of the rotating shaft 3. Therefore, the first contact portion 6 and the second contact portion 7 do not vibrate in the central axis direction. Since the vibration does not occur in this way, the rigid hemisphere 131 moves relatively linearly without bouncing on the test member, so that an accurate wear change can be obtained.

That is, in the embodiment of the present invention, the mechanism itself does not vibrate, and the operated portion 10 coupled to the first contact portion 6 is displaced in the direction displaced by the eccentricity of the first eccentric cam 4. Only a displacement is obtained, so that a linear reciprocating motion is obtained. The reciprocating motion is a highly accurate displacement operation even at a high speed.

Further, in the first eccentric cam 4 and the second eccentric cam 5, the circular outer peripheral portion 43 is freely rotated by the lubricating portion 42 with respect to the circular central portion 41, so that the circular outer peripheral portion 43 is the first abutting portion. 6. Even if it is in contact with the second contact portion 7 , it does not become a load with respect to the rotation of the rotary shaft 3. Therefore, the rotational torque of the motor 2 is efficiently converted into a linear reciprocating motion.

  In this way, the measurement in the measurement unit 13 can be performed with high accuracy without being affected by vibration. Further, since vibration does not occur even when the speed is changed, a reciprocating operation at any speed can be stably obtained with a common mechanism.

In the embodiment of the present invention described above, the first pressing portion 8 and the second pressing portion 9 are formed by two leaf springs 81 and 91, respectively, but the present invention is not limited to this. A single leaf spring 81 or 91 may be used.

Incidentally, also in this embodiment of the invention described above, the first eccentric cam 4, the second eccentric cam 5 is separated into a circular central portion 41 and the circular outer peripheral portion 43 via the lubrication unit 42, the The invention is not limited to this, and the circular center portion 41 and the circular outer peripheral portion 43 are integrated so that the first contact portion 6 and the second contact portion 7 are in sliding contact with the circular outer peripheral portion 43. Also good.

In the above-described embodiment of the present invention, the present invention is applied to the measurement of the degree of wear of the test member. However, the present invention is not limited to this. The present invention may be applied to various things such as measuring a viscosity change caused by being rubbed by 131 .

It is a perspective view of the measuring apparatus in the Example of this invention. It is a top view which expands and shows the eccentric cam part in FIG. It is a top view of the measuring apparatus in the Example of this invention. It is a side view of the measuring apparatus in the Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base 2 Motor 3 Rotating shaft 4 1st eccentric cam 5 2nd eccentric cam 6 1st contact part 7 2nd contact part 8 1st press part 9 2nd press part 10 Actuated part DESCRIPTION OF SYMBOLS 11 Fixing part 12 Screw 13 Measuring part 14 Support stand 41, 51 Circular center part 42, 52 Lubricating part 43, 53 Circular outer peripheral part 44, 54 Through-hole 81, 91 Leaf spring 92 Spacer 131 Rigid hemisphere 132 Support spring 133 Friction force sensor Part

Claims (3)

A rotating shaft rotated by a drive motor ;
A first eccentric cam attached to the rotating shaft;
A second eccentric cam attached to the rotating shaft in a positional relationship opposite to the first eccentric cam;
A first abutting portion arranged in contact with the outer peripheral surface of the first eccentric cam and coupled to the actuated portion;
Wherein relative to the first eccentric cam disposed in contact with the outer peripheral surface of the second eccentric cam at a position facing each other across the rotary shaft, the equal correct weight on the weight of said first contact portion Two abutting portions;
The first abutting portion has a plane parallel to the axis of the rotating shaft, and has one end as a fixed end and the other end as a free end, and the first abutting portion is directed to the first cam. First pressing means formed from a leaf spring having elastic force to press;
The second abutting portion has a plane parallel to the axis of the rotating shaft, the one end is a fixed end and the other end is a free end, and the second abutting portion is attached to the first abutting portion. The second facing the displacement direction
Second pressing means formed from a leaf spring that presses in the direction of the cam with an elastic force equal to the elastic force of the first pressing means and every driving instant ;
E Bei a support spring having a stiffness hemisphere tip, and a frictional force sensor unit base side is attached to the supporting spring, and a measuring unit for measuring the degree of wear of the driven portion,
One end of the rotary shaft is connected on the same axis of the drive motor, and the rotary shaft is rotated by the drive motor,
Arranging the first eccentric cam and the second eccentric cam in order from the driving force side of the rotary shaft in the axial direction;
The rigid hemisphere is pressed against and brought into contact with the actuated portion by the elastic force of the support spring,
The actuated part is worn on the surface by repeating the linear reciprocation of the first abutting part in a state where the rigid hemisphere is abutted,
The measuring apparatus characterized in that the frictional force sensor unit measures a frictional force that changes as the worn state of the operated part progresses . It said first pressing means and said second pressing means, measurement of claim 1 via a spacer, characterized in that it is formed from a set of leaf springs arranged at a predetermined interval Equipment . The first eccentric cam and the second eccentric cam include a circular center portion and a circular outer peripheral portion that rotates concentrically with the circular center portion via a lubrication portion,
The measuring apparatus according to claim 1, wherein the rotating shaft is formed so as to penetrate and be fixed at a position eccentric from a center position of the circular central portion.

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