JPH0421049Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a touch signal probe, which is used in three-dimensional measuring machines, other measuring machines, etc.
This invention relates to a touch signal probe that electrically detects contact with an object to be measured.

[Background technology and its problems]

Conventionally, there has been a demand for a touch signal probe that can measure the size and shape of easily deformed objects such as synthetic resins with high precision and without damaging the objects. To meet this demand, the measurement pressure must be low, the instantaneous operation must be excellent, and the overrun tolerance must be wide. Therefore, it was necessary to improve the conventional touch signal probe in which the probe shaft is biased toward the positioning member by a strong spring and held at a predetermined neutral position.

In order to solve this technical problem, the applicant
In Utility Model Application No. 58-180408, a probe shaft having a contact at one end is rotatably supported on a probe shaft support, and is also used as a probe shaft support. A position regulating means that comes into contact with the probe shaft to prevent free rotation of the probe shaft is provided so as to be able to come into contact with and separate from the probe shaft, and an electric contact for detecting a touch signal is provided at the contact point between the probe shaft and the position regulating means. Normally, the probe shaft and position regulating means are brought into contact with each other by an extremely small force, and the probe shaft is supported in a predetermined posture, and the probe shaft and position regulating means are separated at the same time as the contact contacts the object to be measured. proposed a device that generates a touch signal.

However, the probe configured in this way
Since the device detects electrical continuity or disconnection of a single point of contact, the contact direction of the probe with respect to the object to be measured is inevitably limited to one direction, and measurements of groove width, hole inner diameter, etc. Since it is necessary to bring the probes into contact from two opposing directions, there is a problem in that it is virtually impossible.

[Purpose of invention]

The purpose of this invention is to develop a touch signal probe that can achieve instantaneous operation with extremely low measuring force and a large overrun tolerance even when measuring by touching the probes from two opposing directions. It is about providing.

[Means and actions for solving problems]

In the present invention, a probe shaft having a contact at one end is rotatably supported on a probe shaft support, and a first position regulating means abuts against the probe shaft to prevent rotation of the probe shaft in one direction. is attached to a support body such that it can come into contact with and separate from the probe shaft, and a second position regulating means that comes into contact with the probe shaft to prevent rotation of the probe shaft in a direction opposite to the one direction is supported so that it can come into contact with and separate from the probe shaft. It is made of a weight piece, etc. attached to the body and movable in the axial direction on the other end of the probe shaft, and reverses the magnitude of the weight moment between the contact side and the non-contact side across the shaft support of the probe shaft. A weight moment reversing means for changing the direction of rotation of the probe shaft between the first and second position regulating means is provided, and a first and an electrical contact for detecting a second touch signal.

Accordingly, in order to perform measurement by bringing the probe into contact with the object to be measured from two directions facing each other, the weight moment reversing means is operated to rotate the probe shaft in one direction, and the first position regulating means In this state, the probe is moved in one direction, and the contact of the probe shaft is brought into contact with the object to be measured to generate a touch signal. In addition to changing the
The probe is brought into contact with the position regulating means with a minute force, and in this state, the probe is moved in the opposite direction to the one direction,
This object is achieved by bringing the object to be measured into contact with the contact of the probe shaft and generating a touch signal.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 1 to 3.

1 and 2 show the overall structure of an embodiment of the touch signal probe according to the present invention. In these figures, a support mounting shaft 3 is attached to the upper end side of a conductive probe shaft support 1 The mounting shaft 3 is adapted to be attached to a movable part (not shown) of a measuring machine body in a coordinate measuring machine or other measuring machine. Further, the probe shaft support 1 is provided with a pair of thick plate-like side walls 4 arranged parallel to each other on the lower end side, and between these side walls 4, a conductive probe shaft 2 is connected to the probe shaft 2. It is rotatably provided via a support shaft 5 and pivot bearings 6 and 7, which are arranged along the radial direction of the shaft.

A small spherical contactor 13 is provided at one end of the probe shaft 2, and a weight piece 14 as a weight moment reversing means is provided at the other end. The weight piece 14 is formed into a substantially ring shape, and is screwed into a threaded portion 15 carved in a predetermined range on the outer circumferential surface of the other end of the probe shaft 2. It is possible to move along the direction. At this time, when the weight piece 14 is placed on the support shaft side, the weight moment on the contact side becomes larger than the weight moment on the opposite contact side with the support shaft 5 in between, so that the contact side is downward, that is, the first When rotated clockwise in the figure and placed on the opposite side of the support shaft, the weight moment on the contact side becomes smaller than the weight moment on the opposite side with the support shaft 5 in between, and the contact side moves upward. That is, it is rotated counterclockwise in FIG. In particular, when the weight piece 14 is located closest to the support shaft or closest to the opposite side of the support shaft within its movement range, the absolute values of the differences between the contact side moment and the opposite contact side moment at these positions are equal. It is considered a thing. This makes it possible to easily obtain a constant measurement pressure regardless of changes in the attitude of the probe shaft 2.

Between the side walls 4, a first position regulating means 16A is provided on the upper left side of the support shaft 5 in FIG. The first position regulating means 16A is made of a conductive round rod, and is arranged parallel to the spindle 5, and both ends thereof are attached to the side wall 4 via insulating bushes 17 made of Bakelite or the like. ing. Further, the intermediate position between the first position regulating means 16A, the support shaft 5 of the probe shaft 2, and the weight piece 14 is as follows.
It is possible to make contact with the upper side of the probe shaft 2 in FIG. Here, an electrical contact point 20A for detecting a first touch signal is formed by a contact point between the probe shaft 2 and the first position regulating means 16A.

A second position regulating means 16B having the same structure as the first position regulating means 16A is provided below the first position regulating means 16A between the side walls 4.
Here, the support shaft 5 is connected to the first and second position regulating means 1.
It is located at the same height as the intermediate position between 6A and 16B. The second position regulating means 16B, the intermediate position between the support shaft 5 of the probe shaft 2 and the weight piece 14 can be brought into contact with each other on the lower side of the probe shaft 2 in FIG. Two electrical contacts 20B for touch signal detection are formed.

The support body 1 is provided with a connector 21 on the right side in FIG. 2, and a light emitting diode 22 and a switch 23 as a switching means on the left side. The restricting means 20A, 20B and conductive bolts 25 attached to the support 1 are wired within the support 1. Details of this wiring are shown in FIG. That is, the switch 23 has three terminals and can switch the connection between the terminals 1 and 2 and the connection between the terminals 2 and 3. Contact point 20
The second electrical contact 20B is connected to the terminal 3 via the second position regulating means 16B. On the other hand, the terminal 2 of the switch 23 is connected to one terminal (terminal 5) of the connector 21 connected to the probe shaft 2, and the probe shaft 2 moves between the first and second electrical contacts 20A and 20B.
The support shaft 5 of is connected to the other terminal (terminal 4) of the connector 21. The connector 21 is connected to both terminals of the light emitting diode 22 and to the mounting shaft 3 for grounding (terminals 1, 3 and 2), and is also connected to the controller 30.

Next, these structures will be explained in more detail using the block diagram of FIG. In this figure, the subscripts of each block indicate the terminals of the connector 21 and the switch 23 as switching means, respectively. As mentioned above, the first and second electrical contacts 20A, 20B
is connected to a connector 21 via a switch 23, and a support shaft 5 and a light emitting diode (LED) 22 are connected to this connector 21. As a result, the switch 23 is switched, and the first electrical contact 20A and the connector 21 are connected to each other.
When each contact 20A, 20B is opened by moving the probe shaft 2 away from the first or second position regulating means 16A, 16B while the electrical contact 20B and the connector 21 are connected, the connector 2
A contact opening signal is sent to the controller 30 via 1. On the other hand, the switch 2
A switch detection means 31 is connected to the terminals 1 to 3 of the switch 3, and the switch detection means 31 is configured to send a signal for detecting the switching state of the switch 23 to the controller 30. This controller 30 includes a touch signal detection means 41, a calculation means 42, an LED driving means 43, a correction means 44,
It is composed of a storage means 45. The touch signal detection means 41 detects a contact open signal sent from the connector 21 and sends the signal to the calculation means 42. The correcting means 44 receives the signal from the switch detecting means 31 and determines whether the first electrical contact 20A or the second electrical contact 20B is opened, and changes the second electrical contact. Storage means 45 only when 20B is released
A signal for correcting the dimensional difference between the tips of the contactors 13, that is, the measurement reference dimensional difference D (see FIG. 1), which occurs when measuring by changing the attitude of the probe shaft 2, is sent to the calculation means 42. There is. Arithmetic means 4
A displacement signal from a displacement detector 61 is input to the displacement detector 2.
For example, when the touch signal probe of the present invention is attached to a coordinate measuring machine, it is composed of a linear displacement encoder, etc. that detects the amount of relative movement between the touch signal probe and the main body of the coordinate measuring machine, that is, the amount of displacement. There is. Further, the calculating means 42 receives the signal from the touch signal detecting means 41, calculates the amount of displacement from the displacement detector 61, and sends a signal of the calculated value to the display means 62. At this time, when a signal is received from the correction means 44, the calculated value is corrected using the correction value signal and sent to the display means 62. The LED driving means 43 receives a signal from the calculating means 42 and turns on the light emitting diode (LED) 22 via the connector 21.

Next, the operation of this embodiment will be explained.

First, in order to measure the contact position with the object to be measured by bringing the contact 13 into contact with the object to be measured (not shown) from above, the weight piece 14 is placed on the support shaft side of the probe shaft 2. The probe shaft 2 is brought into contact with the first position regulating means 16A from below with an extremely small force, and further,
Connect terminals 1 and 2 of switch 23. In this state, the probe shaft 2 is lowered to bring the contact 13 into contact with the object to be measured from above. When the contactor 13 comes into contact with the object to be measured, it instantly rises, and the probe shaft 2 rotates counterclockwise in FIG. 1 to separate from the first position regulating means 16A. As a result, the first touch signal detection electrical contact 20A is opened, a detection signal is sent to the touch signal detection means 41 via the connector 21, and the contact between the probe shaft 2 and the object to be measured is electrically detected. The contact position of the probe shaft 2 is displayed on the display means 62 via the calculation means 42, and the light emitting diode 22 is turned on by the LED driving means 43 to display the detection of this contact. At this time, since the switch detection means 31 detects that the first electrical contact 20A is open, the correction means 44 and the storage means 45 calculate the measurement standard dimensional difference D due to the attitude difference of the probe shaft 2. No corrections are made to the measured values.

On the other hand, in order to perform measurement by bringing the contactor 13 into contact with the object to be measured from below, the weight piece 14 is attached to the probe shaft 2.
The probe shaft 2 is placed on the side opposite to the supporting shaft, and the attitude of the probe shaft 2 is changed to the state shown by the chain line in FIG. Then, by switching the switch 23, the terminals 2 and 3 are connected. In this state, the probe shaft 2 is raised to bring the contact 13 into contact with the object to be measured from below, and measurement is performed in the same manner as described above. At this time, the switch detection means 3
1. By the correction means 44 and the storage means 45,
It is detected that the second electrical contact 20B is opened, and the measurement reference dimension difference D of the contactor 13 caused by the change in the attitude of the probe shaft 2 is corrected for the measured value. The correction value is displayed on the display means 62 via the calculation means 42.

According to this embodiment, the probe shaft 2 can be held in a predetermined posture by bringing the probe shaft 2 into contact with the first and second position regulating means 16A, 16B with extremely small force. , the measurement pressure can be made extremely small. Therefore, even objects to be measured that are easily deformed, such as synthetic resins, can be measured with high precision. Furthermore, since the probe shaft 2 is not operated against the biasing force of a strong spring, it has excellent instantaneous operation, which improves the accuracy of spring measurement. The overrun tolerance range is widened, which is convenient for measurement work. Moreover, since the attitude of the probe shaft 2 can be changed by the weight piece 14, measurements can be made from directions facing each other. Therefore, the groove width, hole inner diameter, etc. can be measured. Also,
According to this embodiment, since the weight moment reversing means is the weight piece 14 screwed onto the probe shaft 2,
The touch signal probe can have a simple structure, and the position and measurement pressure can be adjusted accurately. Further, the switch 23, the switch detection means 31, etc. can correct the measurement reference dimension difference D of the contactor 13 that occurs when measuring by changing the attitude of the probe shaft 2, thereby ensuring speed and accuracy of measurement.

In the above embodiment, the weight moment reversing means is the weight piece 14, but the present invention is not limited to this. For example, the probe shaft 2 may be set to the first or second position regulating means 16A, 16B. The probe shaft 2 is placed on the support 1 so as to be brought into contact with a minute force, and when changing the attitude of the probe shaft 2, the probe shaft 2 is attached in the direction away from the first or second position regulating means 16A, 16B. A biasing means such as a spring with a weak force is interposed between the probe shaft 2 and the support body 1, and the probe shaft 2 and the second or first position regulating means 16 are
B and 16A may be brought into contact with each other with extremely small force. Even in such a case, the measurement pressure can be made extremely small and the instantaneous operability can be made excellent, as described above. In addition, the weight piece 14 is used as the weight moment reversal means.
Even if the probe shaft 2 is used, it is not necessarily required to be movable along the axial direction of the probe shaft 2 as in the above embodiment. For example, when the weight piece 14 is not attached, the probe shaft 2 is
The support body 1 is pivotally supported so that the contact side has a larger weight moment than the non-contact side across the contact side,
At all times, the probe shaft 2 is brought into contact with the first position regulating means 16A, but in order to change the attitude of the probe shaft 2, the weight piece 14 is attached to the other end of the probe shaft 2 to reverse the magnitude of the weight moment. It may also be something that allows you to do so. Further, in order to enable the weight piece 14 to reciprocate in the axial direction of the probe shaft 2, it is not necessarily necessary to form the threaded portion 15 on the probe shaft 2. For example, if there is a weight piece on the other end of the probe shaft 2,
4 is provided to be slidable in the axial direction, and can be fixed at any position with a set screw, or a moderation mechanism that can be stopped at a position separated by a predetermined distance in the axial direction between the weight piece 14 and the probe shaft 2. It is also possible to provide a device that allows the position to be changed with a single touch. However, if the threaded portion 15 is formed as in the embodiment described above, the weight piece 14 can be easily moved by a minute amount and the contact force of the probe shaft 2 against the first and second position regulating means 16A, 16B can be reduced. Easy to adjust. Also,
The switch 23 and the switch detection means 31 do not necessarily need to be provided; for example, as shown in FIG.
The second electrical contacts 20A, 20B are respectively connected to different terminals of the connector 210, and a detection signal is also sent to the controller (not shown in FIG. 5) when either of these electrical contacts 20A, 20B is released. In addition, the light emitting diode 22 may be turned on. At this time, any electrical contact 20
Whether A and 20B are released can be determined by the release of electrical contacts 20A and 20B that are energized before the contactor 13 comes into contact with the object to be measured.
The measurement standard dimensional difference is corrected in accordance with this determination. That is, if there is a conductive signal from the terminal 4 of the connector 210, the first electrical contact 20A is closed and the probe shaft 2 is in the solid line state in FIG. 1, and no correction is necessary. If there is a conductive signal from , the second electrical contact 20B is released and the probe shaft 2 is in the state indicated by the chain line in FIG. 1, and correction is required. In addition, in the above embodiment, the case where the measurement is performed with the probe shaft 2 in contact with the first electrical contact 20A is used as a reference, and when the measurement is performed with the probe shaft 2 in contact with the second electrical contact 20B, The measurement standard dimensional difference D is stored in the storage means 45.
However, in the present invention, the measurement reference position is set when the probe shaft 2 is in the neutral position, and the probe shaft 2 moves from this reference position to the first or second electrical contact 20A, 20B. The movement dimension of the contactor 13 when it comes into contact with (D/2), (-D/
2) may be stored in the storage means 45 to correct the measured value. Furthermore, the first and second position regulating means 16A, 16B may be attached to the support body 1 at the upper and lower right sides in FIG. 1, or may be attached at the upper or lower left and right sides,
The location doesn't matter.

[Effect of idea]

According to the present invention as described above, even when measuring by bringing the probes into contact from two opposing directions, it is possible to obtain excellent instantaneous operation and a large overrun tolerance with extremely small measuring force. .

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an embodiment according to the present invention,
2 is a sectional view taken along the line - in FIG. 1, FIG. 3 is a wiring diagram of the embodiment, FIG. 4 is a block diagram of the embodiment, and FIG. 5 is a modification of the present invention. This is a wiring diagram. 1...Probe shaft support, 2...Probe shaft,
5... Support shaft as a shaft support, 13... Contact, 1
4... Weight piece as weight moment reversal means,
16A...first position regulating means, 16B...second
position regulating means, 20A... electrical contact for first touch signal detection, 20B... electrical contact for second touch signal detection, 23... switch as switching means.

Claims (1)

[Claims for Utility Model Registration] (1) A probe shaft rotatably supported on a probe shaft support and having a contact at one end; a first position regulating means that comes into contact with the shaft and prevents the probe shaft from rotating in one direction; a first position regulating means that is attached to a support so as to be able to come into contact with and separate from the probe shaft, and that comes into contact with the probe shaft and prevents the probe shaft from rotating in the one direction; a second position regulating means for preventing rotation in a direction opposite to that of the probe shaft; Weight moment reversal means for changing the rotational direction of the probe shaft between the position regulating means, and first and second touch signals formed at the contact points between the first and second position regulating means and the probe shaft. A touch signal probe characterized by being equipped with an electric contact for detection. (2) Utility Model Registration In claim 1, the weight moment reversing means is provided so as to be movable in the axial direction of the probe shaft on the side opposite to the contactor from the shaft support of the probe shaft, and this movement causes the shaft support to move. A touch signal probe characterized in that it is a weight piece that reverses the magnitude of the weight moment between the sandwiched contact side and the opposite contact side. (3) The touch signal probe according to claim 1 or 2 of the utility model registration claim, characterized in that it is provided with a switching means for electrically switching between the first position regulating means and the second position regulating means. .