JP2001334734A - Positioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positioning device in which the change of positional accuracy of a linear scale caused by the environment in use is suppressed. SOLUTION: This invention is the positioning device on which a sheet scale 2 calibrated at regular intervals is fixed adhesively with an adhesive onto a scale base 1. The adhesive is characterized by 2 Mpa or more in longitudinal shear strength, 10N/10 mm or more in peel strength, D 75 or more in plastic shore hardness and 0.3% or less in swelling caused by the infiltration of an oil-based ink under room temperature. In accordance with this invention, since a solidified adhesive is hardly changed by temperature and humidity, the lowering of positioning accuracy due to the deformation of the scale 2 can be prevented by suppressing the deformation of the scale base 1 and the scale 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position determining device used for a printing device such as a printer and a plotter.

[0002]

2. Description of the Related Art Conventionally, a recording material such as paper is conveyed in a predetermined direction, and an image forming agent such as ink is applied in accordance with an image signal from a recording head running in a direction perpendicular to the recording material to form a printed image. In a known printing apparatus such as a printer or a plotter, a linear scale is provided along a traveling direction of the recording head in order to determine a timing at which the recording head discharges ink during traveling.

[0003] The linear scale is made of, for example, a band-shaped member or a plate-shaped member made of a synthetic resin, and is provided with fine scales (lines or slits) at equal intervals in a direction perpendicular to the running direction of the recording head.

The linear scale reads the scale of the linear scale by transmitting light with an optical sensor such as a photo interrupter installed on a carriage or the like on which the recording head is mounted, and determines the ink ejection timing of the recording head. are doing. Thus, the linear scale is formed using a transparent synthetic resin material in order to transmit light.

[0005] As a fixing method of this linear scale,
A method is employed in which both ends are fixed to a scale base while applying tension in the longitudinal direction.

As another method of fixing a linear scale, a method disclosed in Japanese Patent Application Laid-Open No. 9-234925 is known. The method of fixing the linear scale disclosed in the publication will be described with reference to FIG.

In FIG. 4, a boss 101a provided on a substrate (scale base) 101 of the apparatus main body is fitted with a boss hole 102a provided on a linear scale 102 made of a transparent film or a synthetic resin. The entire surface of the linear scale 102 is placed on the base material 101 on the double-sided tape 10.
3 is used for bonding.

As described above, by fitting the boss 101a provided on the base 101 of the apparatus main body with the boss hole 102a provided on the linear scale 102, the traveling direction of the carriage of the recording head (not shown) and the linear scale Adjustment of the parallelism with the longitudinal direction of 102 becomes easy.

Also, a linear scale 102 made of synthetic resin is used.
Other than the above, a metal linear scale may be used. This linear scale is provided with fine slits at equal intervals in the direction orthogonal to the running method of the recording head, irradiates light to the slits, and reads the light passing through the slits with an optical sensor, whereby the ink of the recording head is Is determined at the timing of discharging the ink.

[0010]

However, in the method of fixing both ends of the synthetic resin linear scale while applying tension, the linear scale itself is easily deformed because the linear scale itself is subjected to tension for a long time. The interval between the scales is widened, and the positional accuracy is degraded.

Further, even if a metal linear scale is employed, if the number of slits is large, the width of the slit is large, or the linear scale itself is long, the rigidity of the linear scale is reduced, and the composite scale is reduced. It is deformed like a linear scale made of resin.

Further, according to the method disclosed in Japanese Patent Application Laid-Open No. 9-234925, the linear scale 102 made of synthetic resin is fixed to the base 101 without directly applying tension, thereby avoiding deformation of the linear scale 102. However, since the entire surface of the linear scale 102 is adhered to the substrate 101 with the double-sided tape 103, the difference in the coefficient of linear expansion between the materials of the substrate 101 and the linear scale 102, the humidity swelling property,
In terms of environmental resistance to the ink scattered in the atmosphere, the double-sided tape 103 is not durable.
Also in the case of 2, it is difficult to secure the positional accuracy.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to provide a position determining apparatus which suppresses a change in the position accuracy of a linear scale due to a use environment.

[0014]

According to the first aspect of the present invention,
What is claimed is: 1. A positioning device comprising a thin plate-shaped scale on which scales are marked at equal intervals is fixed to a scale base with an adhesive, wherein the adhesive has a shear adhesive strength of 2 Mpa or more and a peel adhesive strength of 10 N / 10 mm. As described above, the plastic hardness Shore is D75 or more, and the swelling due to oil-based ink immersion at room temperature is 0.
It is characterized by being 3% or less.

According to the present invention, the solidified adhesive is
Since there is almost no change due to temperature and humidity, deformation of the scale base and the scale can be suppressed, and a decrease in positioning accuracy due to the deformation of the scale can be prevented.

The adhesive has an ink swelling property of 0.3 watts.
Since it is as low as t% or less, even if ink scattered in the use environment of the recording head (not shown) does not change in dimensions, it is possible to prevent a decrease in positioning accuracy due to deformation of the scale from this point. .

Further, in the adhesive layer between the scale base and the scale, by using a scale made of glass or the like which does not transmit moisture, the invasion of moisture from the thickness direction of the scale is prevented. Therefore, it is difficult for moisture to spread, swelling due to water absorption does not occur, and a decrease in adhesion between the scale base and the scale and peeling are unlikely to occur.

According to a second aspect of the present invention, in the position determining device according to the first aspect, the scale base is provided with window holes each having a curved surface shape at both ends along a length direction thereof. It is characterized by the following.

According to the present invention, in addition to the function of the first aspect of the present invention, the scale base is provided with window holes each having a curved surface shape at both ends along the length direction. Even if a shift force is generated between the base and the scale due to a difference in the coefficient of linear expansion, no stress concentration occurs due to this force, and peeling between the scale base and the scale is prevented.

According to a third aspect of the present invention, in the position determining device according to the first aspect, the scale is 70% of its width.
The above is characterized by being fixed to the scale base.

According to the present invention, in addition to the function of the first aspect of the present invention, since the scale is fixed to the scale base at least 70% of its width, an unbonded portion of the scale to which the scale is not bonded is provided. Flatness change and dimensional deformation can be suppressed.

[0022]

Embodiments of the present invention will be described below in detail.

(Embodiment 1) FIG. 1 is a schematic perspective view showing a joint state between a scale 2 and a scale base 1 in a position determining apparatus according to Embodiment 1 of the present invention.

In FIG. 1, a scale 2 is made of a transparent glass strip, and scales 2a are formed at equal intervals in a short direction orthogonal to a longitudinal direction thereof.

On the other hand, the scale base 1 for fixing the scale 2 is made of SUS (stainless steel), and has a window hole (a long hole) 4 formed along its longitudinal direction. This window hole 4
Is less than or equal to 30% of the width W2 of the scale 2 described later (W1 = 3 mm, W2 = 10 m in the present embodiment).
m).

As shown in FIG. 2, one end 4a of the window hole 4 is formed in a semicircular shape whose diameter is the length of the window hole 4 in the short direction. The other end 4b of the window hole 4 is also formed in a semicircular shape having a diameter equal to the length of the window hole 4 in the lateral direction, similarly to the end portion 4a.

When the scale 2 is adhesively fixed on the scale base 1, first, around the window hole 4 formed in the scale base 1, the viscosity is 300 mPa · s, and the shear adhesive strength is 2 Mpa or more (this embodiment). 2.6 Mp in mode 1
a), peel adhesion strength of 10 N / 10 mm or more (12 N / 10 mm in the first embodiment), plastic hardness Shore D of 75 or more (D82 in the first embodiment), swelling 0.3% by immersion in oil-based ink at room temperature The following (Embodiment 1)
In this case, a transparent room temperature-curable epoxy adhesive 3 (0.2%) is applied.

Thereafter, the scale 2 is adhered to the scale base 1 via the adhesive 3, and a load of 50 N is applied so that the scale base 1 and the whole scale 2 are close to each other, for 48 hours at room temperature. The adhesive 3 interposed between the scale base 1 and the scale 2 was cured as described above.

According to the position determining device of the first embodiment,
As described above, due to the adhesive 3 firmly adhered and solidified to the scale base 1 and the scale 2 respectively, a member of the scale base 1 and the scale 2 having a small amount of change due to temperature and humidity, that is, linear expansion A member having a large change amount, that is, a member having a large linear expansion coefficient (scale 2 in the first embodiment) is attracted to a member having a small coefficient (the scale base 1 in the first embodiment).

That is, since the solidified adhesive 3 hardly changes due to temperature and humidity, the scale base 1 and the scale 2
Can be suppressed, and a decrease in the positioning accuracy due to the deformation of the scale 2 can be prevented.

In particular, since the outer circumference of the scale 2 is bonded and fixed to the scale base 1, deformation is uniformly suppressed over the whole.

The end 4 of the window hole 4 of the scale base 1
a and 4b are formed in a smooth semi-circular shape with no corners, so that the scale base 1 when the scale 2 is deformed
There is no portion where the stress concentrates, and peeling of the adhesive portion between the scale 2 and the scale base 1 due to the stress concentration does not occur.

Further, since the adhesive 3 has a low ink swelling property of 0.2 wt%, the dimension does not change even if ink scattered in a use environment of a recording head (not shown) adheres.

Further, for the adhesive layer between the scale base 1 and the scale 2, a glass scale 2 is used.
Is used, moisture is prevented from penetrating from the thickness direction of the scale 2, so that the moisture is hardly spread, swelling due to water absorption does not occur, and the adhesive strength between the scale base 1 and the scale 2 is reduced. And peeling hardly occur.

In the first embodiment, glass is used as the material of the scale 2. However, the material is not limited to glass as long as it is transparent. For example, PET (polyethylene terephthalate) may be used. In this case, the epoxy adhesive 3
By adding 1% of the silane coupling agent to the weight of the adhesive 3, the adhesion to PET can be improved.

Next, as shown in Table 1 below, a sheet made of SUS (scale base 1) and a sheet made of PET (scale 2) were bonded using several kinds of adhesives.
Evaluations were made on the shear bond strength, peel bond strength, and swelling due to immersion.

[0037]

[Table 1]

First, a SUS sheet and a PET sheet were bonded in an environment of a temperature of 25 ° C. and a humidity of 35%.
After being left in an environment of 0 ° C. and a humidity of 25% for 20 hours, it was returned to an environment of a temperature of 25 ° C. and a humidity of 35%.

The bonded SUS sheet and PET sheet were pulled along the surface of the sheet, and the force until the PET sheet was sheared, that is, the shear bond strength was measured. Further, the SUS sheet and the PET sheet which were adhered to each other were pulled so that the surfaces of the sheets were arranged at 90 degrees so as to peel off, and the force until peeling, that is, the peeling adhesive strength was measured.

Further, a lump of the adhesive having a predetermined size was immersed in the oil-based ink for about one month, and the extent of swelling was measured.

When the adhesive 3 of the first embodiment is used,
There were no post-resistance problems for any of the shear bond strength, peel bond strength (90 degrees) and swelling due to immersion.

As comparative examples, as shown in Table 1, each of a comparative adhesive (epoxy-modified silicone-based adhesive) A, a comparative adhesive (epoxy-based adhesive) B and a comparative adhesive (silicone-based adhesive) C was used. The same evaluation was performed using an adhesive.

The comparative adhesives A and C had a swelling of more than 2 wt% due to immersion in oil-based ink, and the comparative adhesive C had a shearing adhesive strength of less than 10 N / 10 mm. Agents A and C also had problems after resistance.

In the first embodiment, the shearing adhesive strength of the adhesive 3 is set to 2.6 Mpa. However, if it is 2 Mpa or more, there is obtained no problem after resistance.

In the first embodiment, the adhesive 3
Was 10 N / 10 mm, but 10 N
If it is / 10 mm or more, no problem is obtained after the endurance.

Further, in the first embodiment, the plastic hardness Shore of the adhesive is set to D82. However, the value is not limited to D82 as long as it is in the range of D75 or more (actually, in the range of D75 to D95).

In the first embodiment, the swelling due to the immersion of the oil-based ink is set to 0.2 wt%.

As described above, according to the first embodiment, it is possible to provide a position determining device capable of suppressing a change in the positional accuracy of the scale 2 in a use environment (not shown) such as a recording head.

(Embodiment 2) Next, a position determining apparatus according to Embodiment 2 of the present invention will be described with reference to FIG.

In FIG. 3, the scale 12 is made of a strip-shaped transparent PET, and graduations 12a are formed at equal intervals in a short direction orthogonal to the longitudinal direction.

On the other hand, the scale base 11 for fixing the scale 12 is made of SUS, and its width W3 in the short direction is smaller than the width W4 of the scale 2 in the short direction (W
3 <W4).

When the scale 12 is adhered and fixed on the scale base 11, the scale base 11 has a viscosity of 750 mPa · s and a shear adhesive strength of 2 Mp.
a, Peel adhesion strength 12N / 10mm, plastic hardness Shore D75, swelling 2% by immersion in oily ink at room temperature
A transparent UV-curable acrylic adhesive 13 is applied.

Thereafter, one side of the scale base 11 in the short direction (the edge of one long side) and the one side of the scale 12 in the short direction (the edge of one long side) are aligned, and the scale base 11 The other side in the short direction of the scale 12 (the edge of the other long side) protrudes from the other side in the short direction (the edge of the other long side).

From the scale base 11 to the scale 12
The protruding amount, that is, the non-adhered portion that does not adhere may be 30% or less of the width W4 of the scale 12 in the lateral direction. In the second embodiment, the width W3 of the scale base 11 is used.
Was set to 7 mm, and the width W4 of the scale 12 was set to 10 mm, so that the width of the unbonded portion was set to 3 mm.

That is, in the scale 12, 70% of the width W4 in the short direction is adhered to the scale base 12, and the width of the unadhered portion is the remaining 30%.

In this state, the scale 12 is attached to the scale base 11 via the adhesive 13, and a tension of 10 N / cm is applied to the scale base 11 and the scale 12 in the longitudinal direction. The whole was irradiated with ultraviolet rays of 4500 mJ / cm ² or more, and the adhesive 13 interposed between the scale base 11 and the scale 12 was instantaneously cured. Other operations of the second embodiment are the same as those of the first embodiment, and therefore, description thereof will be omitted.

The same evaluation as in the first embodiment was performed using the adhesive 13 of the second embodiment. As shown in Table 1, when the adhesive of Embodiment 2 was used, there was no problem after the resistance in any of the shear adhesive strength, the peel adhesive strength, and the swelling due to immersion.

According to the second embodiment, in addition to the effect of the first embodiment, since the ultraviolet-curing adhesive is instantaneously cured by ultraviolet rays and exerts an adhesive force, the scale 12 is hardly displaced, and Since the operation of the subsequent process can be performed immediately, the position determination device can be efficiently manufactured in a short time with little loss of operation time.

Further, since the scale 12 has 70% or more of the width W4 in the short direction adhered to the scale base 11, it is possible to suppress a change in flatness and a dimensional deformation of an unadhered portion which is not adhered. it can.

In the second embodiment, the scale 12
Has a configuration in which a region of 70% of the width W4 in the lateral direction is bonded to the scale base 11, but the present invention is not limited thereto.
It may be in the range of 5%.

According to the present invention described above, the following configuration can be added.

(Supplementary Note 1) In a position determining apparatus in which a thin plate-like scale on which scales at equal intervals are marked is fixed to a scale base with an adhesive, the scale and the scale base have a shear bond strength of 2 Mpa and a peel bond. Strength 10N / 10
A position determining device characterized by being fixed with an adhesive having a swelling of 2 mm% or less by immersion in oily ink at room temperature with a plastic hardness Shore D of 75 mm or more and room temperature. According to this configuration, since the scale and the scale base are fixed with the adhesive having the characteristics, deformation of the scale base and the scale is suppressed, and a decrease in positioning accuracy due to the deformation of the scale is prevented. it can.

(Supplementary Note 2) The width 7 of the thin plate scale
0% or more, 7 mm when the width of the thin plate is 10 mm or more
The position determining device according to claim 1, wherein the above is adhered to a scale base. According to this configuration, it is possible to suppress a change in planarity and a dimensional deformation of an unbonded portion where the scale is not bonded.

[0064]

According to the first aspect of the present invention, swelling due to water absorption can be prevented, there is almost no change due to temperature and humidity, deformation of the scale base and scale can be suppressed, and positioning accuracy due to deformation and peeling of the scale can be reduced. It is possible to provide a position determining device capable of preventing the lowering.

According to the second aspect of the present invention, in addition to the effects of the first aspect of the present invention, it is possible to provide a position determining device capable of preventing separation between the scale base and the scale.

According to the third aspect of the present invention, in addition to the effects of the first aspect of the present invention, there is provided a position determining device capable of suppressing a change in flatness and a dimensional deformation of an unbonded portion where the scale is not bonded. Can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a scale base and a scale of a position determining device according to a first embodiment of the present invention.

FIG. 2 is a partially enlarged perspective view of a scale base of the position determination device according to the first embodiment of the present invention.

FIG. 3 is a perspective view showing a scale base and a scale of the position determination device according to the first embodiment of the present invention.

FIG. 4 is a schematic perspective view showing a method of fixing a linear scale to a substrate in a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Scale base 2 Scale 3 Adhesive 4 Window hole 4a End 11 Scale base 12 Scale 13 Adhesive

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C061 AQ05 BB08 BB28 2F065 AA02 BB13 BB15 EE02 FF16 2F069 AA02 BB40 DD06 DD13 EE04 EE26 GG04 GG07 GG15 GG39 GG52 GG56 HH14 JJ02 JJ11 NN12 NN13 NN13 EA19 EA20

Claims (3)

[Claims] 1. A position determining device in which a thin plate-like scale having scales marked at equal intervals is bonded and fixed to a scale base with an adhesive, wherein the adhesive has a shear adhesive strength of 2 Mpa or more, and a peel adhesive strength. A position determination device characterized by having a plastic hardness Shore of at least 10 N / 10 mm, a plastic hardness Shore of at least D75, and a swelling by immersion in oily ink at room temperature of at most 0.3%. 2. The position determining apparatus according to claim 1, wherein the scale base is provided with window holes each having a curved surface shape at both ends along a length direction thereof. 3. The position determining apparatus according to claim 1, wherein at least 70% of the width of the scale is fixed to the scale base.