JPH0712882Y2 - Length measuring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a length measuring device for measuring a moving distance by relative movement between a main scale provided in a housing and a detection head. In particular, dust, water droplets, water drops, etc. in the housing through the opening for inserting the connecting member formed in the housing.
The present invention relates to improvement of dust-proof / liquid-proof means for preventing entry of oil mist.

[Prior Art] A conventional length measuring device 1a has a housing 3a as shown in FIG.
A pair of dust-proof and liquid-proof sealing members 7a along the opening 14a
Were arranged so that the tip portions 18a thereof are substantially butted. Then, the opening 14a is closed by the butting of the tip end portion 18a of the sealing member 7a, and the closing prevents dust and liquid in the housing 3a.

[Problems to be Solved by the Invention] In the conventional length measuring apparatus 1a, the tip portion 18 of the seal member 7a is used.
The opening 14a is closed in the part where a is in a butt state, and dust, water droplets, water vapor, oil mist, etc. are stored in the housing.
Preventing entry into 3a.

However, between the portion where the tip end portion 18a of the seal member 7a abuts on the connecting member 6a and the abutting portion, a separating gap portion 20a is formed in a portion where the connecting member 6a separates the seal member 7a. Therefore, dust, water droplets, oil mist, etc. enter the housing 3a through the separation gap 20a and affect the displacement detection for length measurement, or damage the length measurement detection means such as the main scale 2a. was there.

This invention was made in view of the above circumstances,
Dust and liquid prevention related to the separation gap that is created between the portion where the tip of the seal member abuts the connecting member and the abutting portion is secured, thus affecting the detection of displacement from dust, water droplets, water vapor, oil mist, etc. (EN) Provided is a length measuring device which is not subject to damage and whose length measuring means is not damaged.

[Means for Solving the Problem] The present invention is directed to a length measuring apparatus including a cover member that moves together with a connecting member and that covers a cleaning gap generated between the connecting member and a seal member. Is.

The detailed structure is such that a scale is internally provided, and a housing provided with an opening along the longitudinal direction of the internally provided scale and a relative movement with respect to the longitudinal direction of the internally provided scale. A detection head that detects the amount of movement thereof, a connection member that is provided by being inserted through the opening of the housing, one end of which is connected to the detection head, and the other end of which is connected to the object to be measured; In a length measuring device including a seal member arranged on both sides of an opening of a housing and having a tip end in abutting contact with the connecting member, the length measuring device is fixed to the connecting portion outside the housing and is in contact with the seal member. The length measuring apparatus is provided with a cover portion that moves together with the connecting portion in a state and that covers a scraping gap portion generated between the connecting member and the seal portion.

[Operation] The covering member covers the separating gap portion generated between the connecting member and the sealing member.

[Embodiment] The present invention will be described in detail based on an embodiment shown in FIGS. However, the present invention is not limited to this embodiment.

As shown in FIGS. 1 to 4, the length measuring device 1 includes a main scale 2, a housing 3, a detection head 4, a calculation display means 5, a connecting member 6, a sealing member 7, and a covering member 8. Has been.

The main scale 2 is disposed and fixed inside the housing 3.

An opening 14 extending in the longitudinal direction is formed on the bottom surface of the housing 3.

The detection head 4 includes an index scale 9 and a light emitting element 1.
0, a light receiving element 11, a preamplifier (not shown), and a holder (not shown) for holding them are mainly configured. The detection head 4 is movable along the main scale 2 in the longitudinal direction (direction of arrow A), and cooperates with the main scale 2 to detect its moving distance when moving relative to the main scale 2. It is a thing.

The calculation display means 5 receives a signal from the detection head 4 and calculates and displays the amount of relative movement between the main scale 2 and the detection head 4. The calculation display means 5 is connected to the detection head 4 by a cable 12. An operation / display panel 13 is provided on the front surface of the calculation display means 5.

The connecting member 6 is arranged in a state of being inserted into the opening 14 formed in the housing 3. One end of the connecting member 6 is connected to the detection head 4 and the other end is connected to an object to be measured (not shown).

Reference numeral 15 is a connecting portion for connecting with the object to be measured, and 16 is a separating neck portion for separating the seal member 7. A lead wire (not shown) from the detection head 4 is attached to the separating neck portion 16 of the housing 3
Through hole 17 for connecting the cable 12 to the outside of the cable
Are formed.

The seal member 7 is made of a flexible synthetic resin and has a substantially cross-sectional shape in a cross section. The seal member 7 is fitted and fixed in a groove 19 provided along the edge of the opening 14 so that the front end 18 is in a butted state to close the opening 14 of the housing 3.

The cover member 8 has a substantially boat shape with a hole at the bottom, and the edge of the hole is fitted into a groove (not shown) provided around the scraping neck 16 of the detection head 4 to detect It is fixed to the head 4. The cover member 8 fixedly arranged in this way is positioned in contact with the seal member 7 and covers the scraping gap portion 20 of the seal member 7 generated by the connecting member 6.

The length measuring device 1 is configured as described above. Therefore, when the length measuring device 1 is used in a room where there is dust, water droplets, water vapor, cutting oil, or other oil mist such as at a work site, the length measuring device 1 is naturally used.
You will be exposed to dust, water vapor, oil mist, etc. Therefore, it is conceivable that dust, water droplets, water vapor, oil mist, etc. enter the inside of the housing 3 through the opening 14.

However, at the portion of the opening 14 where the covering member 8 does not cover the sealing member 7, the tip end portion 18 of the sealing member 7 is in a butted state to close the opening 14. Also, the connecting member 6
A separating gap portion is provided between the separating neck portion 16 and the seal member 7.
Although 20 is generated, the separating gap portion 20 is covered by the covering member 8. Moreover, since the cover member 8 is located in contact with the seal member 7 from the outside of the housing 3,
The separating gap 20 is substantially covered with respect to dust and liquid.

Therefore, the inside of the housing 3 is structured so as to be shielded from the outside by the seal member 7 and the cover member 8, so that dust, water droplets, water vapor, oil mist and the like do not enter the inside of the housing 3. Since the length measuring device 1 has a structure in which dust, water vapor, oil mist, etc. do not enter the housing 3, that is, a structure in which the inside of the housing 3 is completely dustproof and liquidproof, the measurement of the movement amount, That is, the displacement detection is not affected by dust, water drops, water vapor, oil mist, or the like. Similarly, the length measurement detecting means such as the main scale 2, the index scale 9, the light emitting element 10, the light receiving element 11, and the preamplifier are not damaged by dust, water drops, water vapor, oil mist, or the like.

When the detecting head 6 moves in the direction of arrow A with respect to the housing 3, the connecting member 6 connected to the detecting head 6 moves along with the movement, and the scraping caused by the scraping neck portion 16 of the connecting member 6. The gap 20 also moves in the same direction by the same distance. However, as the connecting member 6 moves, the covering member 8
Also moves in the same direction by the same distance, so the
20 continues to be covered by the covering member 8. Therefore, the inside of the housing 3 is kept in a cutoff state from the outside, and the detection head 6
Does not impair the dust-proof / liquid-proof state of the inside of the housing 3.

It is desirable that the shape of the cover member 8 is appropriately selected according to the shapes of the seal member 7 and the detection head 6. That is, for example, in the length measuring device 1, the cover member 8 is configured to contact only the seal member 7, but if higher adhesion is obtained, the cover member 8 contacts the opening edge of the seal member 8 and the opening 14 of the housing 3. It is better to make the shape.

Further, although the covering member 8 is fixed to the separating neck portion 16, it may be fixed to the connecting portion 15.

In addition, although the cover member 8 is fixed to the detection head 6 by fitting and fixing, it may be fixed by band fixing, screw fixing or the like.

Furthermore, the cover member 8 may be made of any material as long as it is flexible, and may be rubber in addition to synthetic resin.

In the length measuring device 1, the length measurement is optically detected,
It may be magnetic.

[Advantages of the Invention] The present invention includes, in addition to the seal member that closes the opening of the housing, a covering member that covers the separation gap formed at the tip of the seal member by the connecting member, and that is attached to the connecting member. By being configured, dust, water droplets, water vapor, oil mist, etc. do not enter through the opening inside the housing, and therefore dust, water droplets, water vapor,
It is a length measuring device that does not affect displacement detection even when used in an environment such as oil mist, and does not damage the length measuring detection means.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention including a partial omission, FIG. 2 is a sectional view taken along the line I--I of FIG. 1, and FIG. 3 is a perspective view of an essential part of this embodiment. FIG. 5 is a sectional view taken along the line II-II in FIG. 3, and FIG. 5 is a view corresponding to FIG. 1 ... Length measuring device, 2 ... Main scale, 3 ... Housing,
4 ... Detection head, 5 ... Calculation display means, 6 ... Connection member, 7
... sealing member, 8 ... covering member, 9 ... index scale, 14 ... opening, 16 ... scraping neck, 18 ... tip, 20 ... scraping gap.

Claims (1)

[Scope of utility model registration request] 1. A housing having a scale therein, and a housing provided with an opening along the longitudinal direction of the scale provided therein, and relatively moving with respect to the longitudinal direction of the scale provided inside the housing. A detection head that detects the amount of movement thereof, a connection member that is provided by being inserted through the opening of the housing, one end of which is connected to the detection head, and the other end of which is connected to the DUT; In a length measuring device including a seal member arranged on both sides of an opening of the housing, the tip of which is in butt contact with the connecting member, the state of being fixed to the connecting portion outside the housing and being in contact with the sealing member And a cover member that moves together with the connecting portion and covers the separation gap formed between the connecting member and the seal portion.