Electric heating – Heating devices – With power supply and voltage or current regulation or...
Reexamination Certificate
2002-01-30
2004-06-15
Jeffery, John A. (Department: 3742)
Electric heating
Heating devices
With power supply and voltage or current regulation or...
C219S469000
Reexamination Certificate
active
06750432
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a heat roller control apparatus, and more particularly relates to a control apparatus for a heat roller for use in a laminator or the like.
2. Description of the Prior Art
FIG. 3
shows a conventional heat roller control apparatus. In
FIG. 3
, a reference numeral
1
denotes a heat roller,
1
A denotes a member, such as a PVC card to be laminated with a thin film
1
B, such as a PET film,
8
a
and
8
b
denote transfer rollers for transferring the member
1
A and the thin film
1
B,
2
a
denotes an actuator, such as a motor for rotating the heat roller
1
,
2
b
denotes an actuator, such as a motor for rotating the transfer roller
8
b
,
3
a
and
3
b
denote driving circuits for driving the actuators
2
a
and
2
b
, respectively,
4
denotes a heater for heating the heat roller
1
,
5
denotes a temperature detecting element, such as a thermistor for detecting a surface temperature of the heat roller
1
,
6
denotes a temperature control circuit for controlling the excitation of the heater
4
,
9
denotes a temperature judging circuit formed of a microprocessor, for example, for judging whether the surface temperature of the heat roller
1
is stable in a predetermined range lower than a first reference signal c
1
indicating the upper limit value, but higher than a second reference signal c
2
indicating the lower limit value,
10
denotes a temperature state indicator for indicating whether the surface temperature of the heat roller
1
is stable in the predetermined range, and
7
a
and
7
b
denote detecting elements, such as photosensors for detecting the presence of the member
1
A, respectively.
FIG. 4
shows a diagram for explaining the surface temperature of the heat roller
1
.
In
FIG. 4
, a reference symbol (a) denotes the first reference signal c
1
indicating the upper limit value of the predetermined range, (b) denotes the second reference signal c
2
indicating the lower limit value of the predetermined range, (c) denotes a temperature signal a outputted from the temperature sensing element
5
, and (d) denotes a temperature judging signal e outputted from the temperature judging circuit
9
. The temperature judging circuit
9
judges whether the temperature signal a outputted from the temperature detecting element
5
is in the predetermined range and maintained continuously for a predetermined setting period of time t
1
. Further, the temperature judging circuit
9
outputs the temperature judging signal e of low level “L” in case that the temperature signal a outputted from the temperature detecting element
5
is out of the predetermined range, or that the temperature signal a is in the predetermined range, but is not maintained continuously for the predetermined setting period of time t
1
. The temperature judging circuit
9
outputs the temperature judging signal e of high level “H” in case that the temperature signal a is in the predetermined range and maintained continuously for the predetermined setting period of time t
1
.
The actuator
2
b
is driven by the driving circuit
3
b
when the detecting element
7
a
detects the presence of the member
1
A and the driving circuit
3
b
receives a first detecting signal b
1
outputted from the detecting element
7
a
. The actuator
2
b
is not driven by the driving circuit
3
b
when the temperature judging signal e is low level “L”. The adhesive strength of the member
1
A becomes small or the member
1
A is deformed if the hot melt coating is carried out in the state that the surface temperature of the heat roller
1
is out of the predetermined range. The member
1
A and the thin film
1
B are transferred to the heat roller
1
by the rotation of the transfer roller
8
b
when the level of the temperature judging signal e is “H” and the actuator
2
b
is driven. The heat roller
1
is rotated when the actuator
2
a
is driven by the driving circuit
3
a
irrespective of the state of the temperature judging signal e or the first detecting signal b
1
outputted from the detecting element
7
a
, so that the member
1
A and the thin film
1
B are held by the transfer roller
8
a
and the heat roller
1
, and the hot melt coating is carried out while they are transferred. The actuator
2
b
is deenergized when the member
1
A and the thin film
1
B are passed through the detecting element
7
b
and the driving circuit
3
b
receives a second detecting signal b
2
outputted from the detecting element
7
b.
The transfer of the member
1
A is not carried out even if the presence of the member
1
A is detected and the surface temperature of the heat roller
1
is in the predetermined range because the temperature judging signal e is low level “L” until the predetermined time t
1
has been passed.
Thus, the time t
1
becomes an idle time.
SUMMARY OF THE INVENTION
Accordingly, it is an object of this invention to provide a heat roller control apparatus free from the above defects.
It is another object of this invention to provide a heat roller control apparatus wherein a variation of a temperature signal outputted from a temperature detecting element is detected at a predetermined interval, and a temperature judging signal of high level is produced so that a member to be laminated with a thin film is transferred for hot melt coating, if the variation of the temperature signal is smaller than a predetermined value when the temperature signal reaches in a predetermined range.
According to a heat roller control apparatus of this invention, the idle time after a surface temperature of a heat roller has reached to the predetermined temperature range can be shortened.
A heat roller control apparatus according to the present invention is characterized by comprising a heat roller for hot melt coating a thin film on a member, a heater for heating the heat roller, temperature detecting means for detecting the surface temperature of the heat roller, temperature control means for controlling the heater according to a temperature detecting signal obtained from the temperature detecting means, and temperature judging means for producing a temperature judging signal for judging the state of the surface temperature of the heat roller according to the temperature detecting signal, wherein the temperature judging means calculates a variation of the surface temperature of the heat roller from the temperature detecting signal every predetermined time and judging the stability of the hot melt coating by the variation of the surface temperature of the heat roller when the temperature detecting signal reaches into a predetermined temperature range.
A heat roller control apparatus according to the present invention is characterized by comprising a heat roller for hot melt coating a thin film on a member, a heater for heating the heat roller, temperature detecting means for detecting the surface temperature of the heat roller, temperature control means for controlling the heater according to a temperature detecting signal obtained from the temperature detecting means, and temperature judging means for producing a temperature judging signal for judging the state of the surface temperature of the heat roller according to the temperature detecting signal, wherein the member to be attached with the thin film is transferred only when the surface temperature reaches into a predetermined temperature range and a variation of the surface temperature of the heat roller is smaller than a predetermined value.
The temperature judging means is a circuit comprising an A/D converter, three comparators, an AND gate, two registers, an oscillator, a subtracter, two frequency dividers, and two inverters.
Other object and advantages will become apparent from the following description of the preferred embodiments taken in conjunction with the accompanying drawings.
REFERENCES:
patent: 4868368 (1989-09-01), Araki
patent: 5140132 (1992-08-01), Shiokawa
patent: 5365314 (1994-11-01), Okuda et al.
patent: 5436431 (1995-07-01), Tsuji et al.
patent: 5798501 (1998-08-01
Boyle Fredrickson Newholm Stein & Gratz S.C.
Japan Servo Co. Ltd.
Jeffery John A.
LandOfFree
Heat roller control apparatus with roller surface... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Heat roller control apparatus with roller surface..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heat roller control apparatus with roller surface... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3359398