JPS61130147A - Sheet material grip device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of erroneous and poor grip of a sheet material, by a method wherein an uniform and continuous fluctuation in the response lag of a resist mechanism is corrected to minimize unevenness in the feed position of the sheet material. CONSTITUTION:A sheet material 8 is fed in a direction D, and is guided to a nip formed by resist rollers 12 and 13. The rollers 12 and 13 are rotated by means of a variable driving means 18. The sheet material 8 is brought to a stop right before a grip position once, and is waited till a grip point of time. The waiting position is detected by photosensor 17a and 17b. For a following grip sequence, a time between the feed of the sheet material 8 and a stop once made is corrected to a proper value at each grip sequence. This, even if an uniform and continuous change in the response of the resist mechanism part is produced due to a change in motion environment, enables the stop position of the sheet material to be adjusted within a given range. This ensures a grip of the sheet material during high speed feed by control at a following stage.

Description

[Detailed description of the invention] [Technicality! ? ] The present invention relates to a sheet material gripping device, and relates to an image recording device η having a rotating body that supports a sheet material, for example, a device that records an image on a sheet material supported by a cylindrical rotating body by a thermal transfer method or an inkjet method, and a photoreceptor. A color device that constitutes the output unit of a color electrophotographic copying device or a computer facsimile using the same method, in which a developed image obtained by developing an electrostatic latent image formed on the top with colored toner is multiple-transferred onto a sheet material carried on a transfer drum. A recording device, a sheet material that can be applied to a thermal transfer image recording device, an electrophotographic image recording device, etc. in which a rotating body carries a sheet-like member other than the sheet material for obtaining the final image, such as a heat-sensitive ink sheet or a photosensitive master sheet. This invention relates to a grip device.

[Prior Art] For example, when multiple images on a photoconductor are transferred onto a single sheet material, as in a color copying machine, the sheet material is wrapped around a transfer drum that rotates in contact with the photoconductor, and the sheet material is transferred to the photoconductor. A common method is to perform multiple transfer by rotating the transfer drum multiple times.

When winding a sheet material around such a transfer drum, the leading edge of the sheet material is gripped by a gripper on the transfer drum. In addition, in image recording apparatuses using a thermal transfer method or an inkjet method, a two-dimensional image is created by rotating a sheet material on a rotary carrier and scanning the thermal transfer head or inkjet nozzle facing the sheet material in the axial direction. There is a method of obtaining the sheet material, and in this case as well, the leading end of the sheet material is often gripped by a gripper on a rotating carrier.

In addition, when a sheet-like member other than the sheet material from which the final image is to be obtained is carried on a rotating body for reasons related to the image forming process, it is common to similarly grip the sheet-like member with a gripper on the rotating body. .

The grip and par of the rotary carrier can be opened when the rotary carrier is at a predetermined rotation angle, and when gripping, the sheet material is synchronously advanced into the gripper, and then the gripper - is closed and the grip is completed.

Synchronization with respect to the advance of the sheet material has been performed by a pair of registration rollers that are in contact with each other and are capable of rotating and stopping at two stages of circumferential speed using a clutch mechanism.

That is, the sheet material supplied from the sheet material supply means is guided by the guide while receiving the conveying force of the conveying means,
It reaches the nip of the registration roller, which is temporarily stopped. At this time, the leading edge of the sheet material contacts the nip portion of the registration rollers, and the rear end of the sheet material receives the conveying force of the conveying means, so the sheet material bends and forms a loop, while the leading edge of the sheet material contacts the registration rollers. Since the sheet material contacts the nip portion uniformly in the axial direction, the skew of the sheet material is corrected.

Thereafter, the pair of registration rollers rotate at a circumferential speed similar to the circumferential speed of the rotary carrier, that is, at a second speed, and pass the leading end of the sheet material. When the registration roller rotates a predetermined amount from a stopped state, the gripper of the rotating carrier
is in an open state and has reached a position where it can grip the sheet material that has entered from the registration rollers. At this moment, the registration roller rotates at a first speed that is approximately twice the second speed, and sends out the sheet material so as to catch up with the gripper, which moves with the rotation of the rotary carrier, and reaches the grip portion. After this, the gripper closes and the grip is completed. On the other hand, the registration roller returns to the second speed again so as to wind the seed material onto the rotary carrier without slack, and feeds out the sheet material at a speed approximating the circumferential speed of the rotary carrier.

The drive control of the registration rollers described above is performed based on a clock pulse signal that is synchronized with the rotation of a rotary carrier that rotates at a constant speed. It remains unchanged.

(Problems to be Solved by the Present Invention) By the way, the distance over which the sheet material is fed from the start of driving the registration roller until the registration roller rotates at the second speed depends on the material of the sheet material and the operating environment. , changes due to age and wear of the drive unit, etc. In other words.

l) The time from when the drive signal is issued while the registration rollers are stopped until the registration rollers start rotating at a predetermined speed. 2) The time from when the leading edge of the sheet material is just before the nip of the registration rollers until the registration rollers start rotating. Time until it is caught in the nip of the registration roller. 3) Time from when the rotation speed switching signal is issued until the rotation of the registration roller rises from the second speed to the first speed.

When the gripper of the rotary carrier has a grip error, the position of the leading end of the sheet material delivered from the registration rollers differs depending on the grip of each sheet material. In particular, this positional variation becomes uniform and continuous for each grip of the sheet material as the temperature rises within the image recording apparatus. This causes a deviation in the relative positional relationship and time relationship between the sheet material and the gripper on the rotary carrier, resulting in a grip error or grip failure, resulting in an abnormal situation such as not being able to obtain a recorded image.

[Objective] The object of the present invention is to solve the above-mentioned conventional problems, correct uniform and continuous fluctuations in the response delay of the registration mechanism, and minimize variations in the sheet material delivery position by the registration rollers. The object of the present invention is to improve reliability in gripping sheet materials.

[Structure of the Invention] The present invention provides a rotary carrier that rotates while supporting a sheet material, a grip means that grips the sheet material on the rotary carrier,
A feeding means for feeding the sheet material to the gripping means, a driving means for stopping the feeding means at a predetermined timing after driving the feeding means, and then driving the feeding means again, and a driving means for driving the sheet material at a position when the feeding means is temporarily stopped. and a control half-immersion to control the timing accordingly.

[Example] Fig. 1 is a diagram of a first embodiment showing the configuration of an image recording apparatus to which the present invention is applied, Fig. 2 is a diagram showing a specific example of the mechanism of the variable speed drive means, and Fig. 3 is a diagram showing a sheet material. Fig. 4 is a time chart showing an example of the correspondence between registration roller drive and sheet material passage detection half-submerged detection signal; It is a flow chart of an example.

First Embodiment> As shown in FIG. 1, the rotary carrier 6 normally rotates at a constant speed in the direction of arrow B, and is capable of holding the sheet material 8 on its outer peripheral surface. The gripper 9 is arranged on the surface of the one-rotation carrier 6, and separates the sheet material 8 from the one-rotation carrier 6 immediately before gripping the leading end of the sheet material 8 approaching from the circumferential direction or after image recording is completed. It is open only when the switch is open, and remains closed at other times. Although the opening/closing mechanism is not shown, it is a gripper that rotates together with the rotary carrier 6 when a cam, which is disposed inside the rotary carrier 6 so as not to follow the rotation thereof, moves in the axial direction by the operation of the plunger. A cam follower integrally fixed to the gripper 9 comes into contact with the cam, thereby opening the gripper 9. A torsion coil spring is applied to the rotating shaft of the gripper 9, and accumulates a biasing force in the direction of closing the gripper 9 when the gripper 9 is in an open state. When the cam follower passes through the contact position with the cam as the rotary carrier 6 rotates, the gripper 9 is brought into a closed state by the restoring force of the spring.

On the other hand, a sheet material supply means (not shown) supplies the sheet material 8 in the direction indicated by the arrow. In order to guide the sheet material 8 to the nip portion of the registration rollers 12 and 13, the registration rollers 12.
There is a guide on the upstream side of the transport path of No. 13! 0 and 11
is located. The registration rollers 12, 13 are brought into contact with each other under suitable pressure, as indicated by arrows C and C', respectively.
It can rotate at the same speed in the force direction, and its rotational drive is supplied from the variable speed drive means. This variable speed drive means! The mechanism 8 will be described later, but its function is to receive driving force from the drive source 2o, and to control the rotation at a second speed that is approximately the same as the peripheral speed of the rotary carrier 6 by a signal from the control means 19, which will be described later. It can be switched to two rotational speeds, including a first speed that is approximately twice the circumferential speed of the carrier 6, and can also be floated in rotation.

Regarding the conveyance direction of the sheet material 8, the registration rollers 12.
There are guides 14 and 15 on the downstream side of the registration rollers 12 and 13, which guide the sheet material 8 carried out from the registration rollers 12. There are apertures 14a and 14b arranged at intervals, and the guide 15 also has an aperture 15 at a position facing the apertures 14a and 14b.
a and 15b are provided.

A lamp 18a is arranged above the opening 14a, and a lamp 18b is arranged above the opening 14b.
, 18b are fixed to the main body of the image recording apparatus.

At the bottom of the opening 15a, the light from the lamp lea is transmitted through the opening 14.
A first optical sensor 17a is arranged at a position where it can receive light through the opening 15a and the first optical sensor 17a. Second optical sensor 17
b is similarly connected to the lamp ta through the openings 14b and 1.5b.
Light b can be received.

When the sheet material 8 is placed between the guides 14 and 15, the light from the lamp lea is blocked, so the first light sensor 17
The presence of the sheet material 8 in the region connecting the apertures 14a and 15a between the guides 14 and 15 can be detected by the output signal of a. The second optical sensor 17b can also detect the same.

The output signals of the optical sensors 17a and 17b are transmitted to a control means 13 which also controls the sequence of the main body of the image recording apparatus.

The control means 18 includes a CPU, Roll, RAM, and optical sensor 1.
7a.

A comparator that binarizes the output of 17b, each comparator, variable speed drive means 18, and clock pulse generation means 50
and an I10 boat connected to the gripper operating section,
The circuit section controls the variable speed drive means 18 based on the clock pulse and calculates the parameters that determine the drive time.

Further, when the movement of the sheet material 8 is stopped due to the rotation and levitation of the registration rollers 12 and 13, the control means 18 determines whether the leading edge of the sheet material 8 is at the position of the optical sensors 17a and 17b based on the output signal. obtain.

On the other hand, a pulse signal from a clock pulse generating means 50 that emits a pulse signal synchronized with the driving of the rotary carrier 6 is transmitted to the control means 19, and the control means 19 controls the gripper 9 according to the number of pulses from the reference position of the rotary carrier 6. 0 that can determine when the grip reaches the grip possible position and the grip end position.
The rotation timing of the rotary carrier 6 is set so that the gripper 9 reaches the grip position 11H after the sheet material 8 has stopped, and just before this, the control means 18 acts on the variable speed drive means 18, The sheet material 8 which has been in a stopped state is fed out toward the gripper 8 at a first speed. Therefore, the accuracy of the floating position is important for the reliability of the grip, and if the permissible range is represented by a in the figure, the optical sensors 17a and 17b are within the range a with a distance expression.

The center of range a, that is, the position with the highest grip reliability is the intermediate position between both sensors.

FIG. 2 is a diagram showing a specific example of the mechanism of the variable speed drive element 1'l18. As shown in FIG. 2, the registration rollers 12 are rotatably supported by a side plate 21 of the recording apparatus main body via bearings 22, and similarly, the registration rollers 13 are supported by the side plate 21 via bearings 23. A gear 24 is fixed to the metal core part 12A of the registration roller 12, and a gear 25 is fixed to the metal core part 13^ of the registration roller 13, and each gear has the same number of teeth and meshes with each other. A sprocket 27 is rotatably held at the outer (left side) tip of the side plate 21 of the core metal portion 13A, and a spring receiver 2B is fixed to the core metal portion 13A adjacent thereto. Body part 2 of sprocket 27
7A and the body 28A of the spring holder 26 have the same outer diameter, and a clutch coil spring 2B is attached to the outside of both cavities, and the clutch coil spring 28 is normally tightened by force. Accordingly, the rotational torque of the sprocket 27 can be transmitted to the spring receiver 2B. Clutch coil: Although not shown, one end of the f-spring 28 is fixed to one end surface of the control ring 29, so by restraining the rotation of the control ring 29, the clutch coil spring 2B is also restrained, and the sprocket 27 is in a predetermined direction (the tightening force of the clutch coil spring 28 is relatively relaxed), the clutch coil spring 28 no longer transmits the rotational torque from the sprocket 27 to the spring receiver 2B.

The lever 30 is rotatably supported by a shaft 31, and is normally given a clockwise rotational force by the biasing force of a tension spring 32, so that one tip 30A of the lever 30 comes into contact with the control ring 29. , which is constrained. The other end of the lever 30 is connected to a second plunger 33, and when the second plunger 33 is energized by a signal from the control means 19, the lever 30 rotates counterclockwise and the control ring 29
The rotational torque from the sprocket 27 can be transmitted to the spring receiver 28 by releasing the restraint.

The shaft 34 is rotatably supported by the side plate 21 via a bearing 35, and the +i! A gear 3B having twice the number of teeth as the gear 25 is fixed on the ll (right) side. On the other hand, on the shaft 34, a sprocket 37 having the same number of teeth as the tin rocket 27 is held at the tip of the outside (left side) of the side plate 21, and a spring receiving fitting 38 is fixed adjacent to this.

The body portion 37A of the sprocket 37 and the adjusting portion 38A of the spring holder 38 have the same outer diameter, and a clutch coil spring 3s is installed on the outside of both body portions. Attachment is by force to tin location 2 to 37
The rotational torque of can be transmitted to the spring holder 38. Although one end of the clutch coil spring 39 is not shown, the control ring 4
0, by restraining the rotation of the control ring 40, the clutch coil spring 38 is also restrained, and the tin rocket 37 is rotated in a predetermined direction (the tightening of the clutch coil spring 3! If the force is relatively loosened), the clutch coil spring 39 will no longer transmit the rotational torque from the sprocket 37 to the spring receiver.

The lever 41 is rotatably supported by a shaft 42, and normally a clockwise rotational force is applied by the biasing force of a tension spring 43, so that one tip 41A of the lever 41 comes into contact with the control ring 40. This is restricted. Lever 41
The other end of the lever 41 is connected to a first plunger 44, and when the first plunger 44 is energized by a signal from the control means 19, the lever 41 rotates counterclockwise, and the control ring 4
0 can be released and the rotational torque from the tin rocket 37 can be transmitted to the spring receiving metal fitting 38.

The shaft 45 is rotatably supported by the side plate 21 via a bearing 4B. A gear 47 that meshes with the gear 38 is on the shaft 45.
is supported via one-way clutch +50,
This one-way clutch 150 is engaged when the rotational speed of the gear 47 is higher than the rotational speed of the shaft 45, and the gear 47 is engaged.
is transmitted to the shaft 45, and when the gear 47 is stopped, the shaft 45 can freely rotate in the rotational direction. Further, a gear 48 that meshes with the gear 25 is fixed to the shaft 45. Gear 47 and gear 48 have the same number of teeth.

The sprocket 27 and the sprocket 37 are provided with a drive source 2.
A chain 48 that obtains driving force from zero is attached.

According to the above configuration, when the first plunger 44 is in the OFF state and the second plunger 33 is in the ON state, the registration rollers 12.13 rotate at the rotational speed of the sprocket 27, that is, the second speed. Incidentally, the rotation of the shaft 45 in conjunction with this is controlled by the gear 36. Axis 3
The transmission to the 4th class is cut off, and the drives of both systems do not interfere.

Further, when both the first plunger 44 and the second plunger 33 are in the ON state, the driving force from the sprocket 37 is transmitted to the registration rollers 12 and 13, and the gear 36 and the gear 25 have a tooth count of 2:1, so that Both rollers 12,13 rotate at twice the speed of the tin rocket 37.

At this time, the spring receiver slides on the metal fitting 28 and the coil spring 28 for the spring clutch, so that the drives of both systems do not interfere.

Hereinafter, the operation of this embodiment will be explained based on FIGS. 3 and 4.

After powering on the image recording device, in step 200,
The pulse of the clock pulse generation means 50 required for the registration rollers 12 and 13 to start driving after removing the skewed sheet material 8 and to temporarily feed the sheet material 8 to the middle of the first and second sheet material passage detection means. The number nd is set to R in the control means 19.
The initial value n0 read from the OM is set, and it is secured at a predetermined location in the RAM in the means la.Next, in step 201, the start of image recording is determined based on an external command for image recording. Next, in step 202, external initial settings within the image recording apparatus are performed, and in relation to the sheet material grip, the first and second plungers 33,
34 is turned off, the rotation of the registration rollers 12 and 13 is stopped, and the carrier 6 starts to rotate one rotation in the direction B. Then,
In step 203, when the one-rotation carrier 6 is at a predetermined rotation angle, the sheet material 8 is fed in the direction of the arrow mark (FIG. 1) toward the registration rollers 12 and 13, and at time t0, the sheet material 8 is fed to the registration rollers 12 and 13. reach the nip. The registration rollers 12 and 13 are not rotating at this point, and while the sheet material 8 is being pushed by the sheet material supply means, its tips uniformly abut in the axial direction of the knee portions of the registration rollers 12 and 13. Therefore, the skew is removed.0 Next, the process proceeds to step 204.1 At time t1, the second plunger 33 is turned on, and the registration roller 1 is turned on at the second speed.
2° 13 is started, the sheet material 8 is passed between both registration rollers 12 and 13, and sent out between the guides 14 and 15. Next, in step 205, in order to stop the registration rollers 12 and 13 almost at the same time as the second plunger 33 turns on, an initial value is set as the pulse count number N I N-0, At step 207, pulses are counted until the number of pulses generated from the clock pulse generating means 50 matches the provisional sending equivalent pulse nd.Next, the process proceeds to step 208, and when the counting ends at time 2, the second plunger 33 is turned off, the registration rollers 12 and 13 are stopped, and the movement of the sheet material 8 is also stopped at the same time.

Next, proceeding to step 209, the first optical sensor 17a
It is determined whether or not the sheet material 8 is detected. If it is detected, the process proceeds to step 210. There, it is determined whether or not the sheet material 8 is detected by the second optical sensor 17b. Proceeds to step 210,
That is, when the first optical sensor 17a detects the sheet material 8 and the second optical sensor 17b does not detect the sheet material 8, the leading end of the sheet material 8 is between the two sensors 17a and 17b.

On the other hand, in step 209, when the optical sensor 17a does not detect the sheet material 8, it means that the leading edge of the sheet material 8 has not reached between both sensors. RA by adding the preset correction width Δn1 to the provisional sending time pulse number nd.
The sheet material M is secured at a predetermined location, the temporary feeding time is lengthened for the next sheet material grip sequence, and the process proceeds to step 213.

Moreover, if the optical sensor 17a detects the sheet material 8,
When the process proceeds to step 21G and the second optical sensor 17b detects the sheet material 8, it means that the leading edge of the sheet material 8 has passed between both sensors, and in this case, step 2
12, the preset correction width Δn2 is subtracted from the provisional delivery time pulse nd, the result is secured at a predetermined location in the RAM, the provisional delivery time is shortened for the next sheet material grip sequence, and the process proceeds to step 213. Proceeding to step 213, the sheet material 8 is waited at the stop position until the gripper 3 of the one-rotation carrier 6 starts to be opened at time t3.Then, the process advances to step 214, and the gripper 3 is completely opened. At time t4, immediately before time t5, the first and second plungers 33 and 44 are turned on, and the sheet material 8 is fed out at speed IF, and at time t5, when the gripper 3 is completely opened, it is at the predetermined grip position. Let it reach E.

Immediately after this, proceeding to step 215, at time t6,
Move the gripper to the closed state. Immediately after this, the process proceeds to step 216 at time t7.

By turning on the first plunger, switching the feeding speed of the sheet material 8 to the second speed, and feeding the sheet material 8 at the same speed as the circumferential speed of the rotary carrier 6, the sheet material 8 is completely lifted at time 0 1n to prevent sagging. Gripper 9 is closed. Thereafter, in step 217, the image is recorded, and in step 218, after post-processing, the process returns to the previous stage of the next image recording sequence.

Step 211.tiri times in sequence. Alternatively, if the number of pulses corresponding to the provisional sending time is modified in step 212, the next sequence will follow this.

2nd Embodiment> In the 11th embodiment, it was possible to modify the equivalent number of pulses for the time from when the registration roller started rotating to when it once stopped. Three sheet material detection points are installed between the
The number of pulses corresponding to the time from when the most upstream detection means in the feeding direction detects the sheet material until the leading edge of the sheet material is located between the other two detection means and stopped is adjusted. Also good.

In this case, compared to the above embodiment, the time variation in the leading edge of the sheet material passing between the registration rollers is corrected #! (
Δnl+Δnz), the equivalent number of pulses m,
1 is easy to stabilize.Also, in the above embodiment, the initial setting value n0 of the equivalent pulse was explained as being read from the ROM, but it may also be inputted from an external switch, etc., and in this way, the initial setting value n0 of the corresponding pulse is read from the ROM. , n6 can be varied by operating a switch. Similarly, the above is possible with the correction width ΔnI+Δn2.

Figure $5 is a flowchart showing an example of an operation when automatically changing the correction width, Δnl+Δn2. For each i-(M-1)th sheet material grip going back from the i-th sheet material grip, the outputs of the first and second optical sensors after feeding the sheet material plate are binarized, and each result is It is ensured that the Ai and Bi addresses in the RAM are reserved each time. The value in RAM when the sensor detects the sheet material is 1. If the value when no detection is detected is set to 0, if the stopping position after feeding the sheet material is always within the specified range, Ai will be I, Bi
continues to be O.

However, if the stop is placed upstream of the first optical sensor, step 21 of the provisional sending time equivalent pulse correction is performed.
1, if it is continuous even through 1, as shown in Figure 6, <Ai,
The stored value of Bi is 0. O is continuous, which means that the correction width Δn1 is too small. In addition, if the stop downstream of the second optical sensor continues even through step 212 of correcting the pulse corresponding to the provisional sending time, the stored values of Ai and Bi are 1.1 as shown in FIG. Continuously, correction width Δn2
means it's too small.

Furthermore, when the stop position of the leading end of the sheet material is continuously switched between the upstream side of the first optical sensor and the downstream side of the second optical sensor for each grip, the eighth
As shown in the figure, the stored values of Ai and Bi are (o, o), (t
, t), (o, o), ... are the same, and (0, 0) and (1, 1) are swapped for each grip, which means that the correction width Δnl + Δn2 is too large. .

Therefore, if any of the phenomena occurs M times in a row in each case, the flow shown in FIG. 5 may be performed for each grip sequence regarding the correction width Δnl+Δn, that is, step 301 ~304 is a step of determining whether the stored value of Ai and the stored value of Bi from the i-th sheet material grip to the i-(M-1)th sheet material grip are equal for each grip. If they are equal, it means that one of the phenomena shown in Figures 6 to 8 has occurred in the sampling of M sets.If there are unequal stored values in the 6M sets that proceed to the subsequent flow, this step is executed. be jumped.

Step 305 is to compare only the stored value Ai of the i-th grip and the stored value A1-1 of the i-1st grip, and if the two values are equal, the phenomenon shown in FIG. 6 or FIG. , it can be determined that the phenomenon shown in FIG. 8 may occur if they are not equal, so one branch is taken here. Steps 306 to 308 are from the i-1st to the i-(M-1)th
This is to judge whether the stored values Ai at the time are all equal, and if considered in combination with step 305, it is possible to judge if the M sampling values Ai are equal. This means that one of these phenomena is occurring. On the other hand, if even one of the M sampling values ^i is unequal, subsequent steps are jumped. Step 310 is to judge whether Ai of the first grip is 1 or not. If A15l, the phenomenon shown in FIG.
This means that the phenomenon shown in the figure is occurring. Therefore, if the phenomenon is shown in Figure 6, the correction width Δnl is increased by multiplying Δn1 by α, where α>1, and if it is the phenomenon shown in Figure 7, β>
The correction width Δn2 is increased by multiplying Δn2 by β, which is 1.

On the other hand, steps 313 to 316 are for determining whether Ai from the i-1th time to the i-(M-1)th time is changed each time.
05, M sampling values A
It is possible to determine if i is swapped for each grip, and if it is determined in this way, the phenomenon shown in FIG. 8 has occurred, so in the subsequent step 317, the correction width Δn++ is
Multiply Δn2 by γ, ε such that γ<1.0<sakul,
Decrease the correction width Δn++Δn2. On the other hand, step 3
If the values of Ai are not alternated in step 14, step 317 is jumped. Therefore, according to this embodiment, the number nd of pulses corresponding to the provisional delivery time is automatically corrected so as to be easily stabilized. In this example, the numbers α, β, γ, and ε are multiplied, but an appropriate number of pulses may be added or subtracted.

[Effects] According to the present invention, in the gripping method in which the sheet material is temporarily stopped just before the grip and waits until the point of grip,
The standby position is detected, and the time from feeding the sheet material until it is temporarily stopped for the next Glyphs sequence is corrected to be appropriate for each grip sequence, so the response of the registration mechanism can be adjusted depending on changes in the operating environment. Even if uniform and continuous fluctuations occur, the stopping position of the sheet material can be kept within a predetermined range. That is, the relative positional relationship between the sheet material and the gripper on the rotary carrier can always be maintained within a limited range, and grip can be ensured during high-speed delivery in subsequent operations. Further, variations between individual image recording devices can be corrected, and reliability of the gripper can be further improved.

[Brief explanation of drawings]

FIG. 1 is a diagram of a first embodiment showing the configuration of an image recording device to which the present invention is applied, and FIG. 2 is a diagram showing a specific example of the mechanism of a variable speed drive means. FIG. 3 is a flowchart showing an example of operations from sheet material supply to gripping. FIG. 4 is a time chart showing an example of the correspondence between the drive of the registration roller and the detection signal of the sheet material detection means; FIG. 5 is a flowchart of the second embodiment regarding correction of the provisional feed time; FIGS. FIG. 8 is a diagram showing the state of stored values in the RAM. 6...Rotating carrier. 12.13... Registration roller, 17... Sheet material passage detection means, 18... Variable speed drive means, 19... Control means, 50... Clock pulse generation means. Figure 4 to tt t2 t4 Jtl Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Scope of Claims] 1) A rotary carrier that rotates while supporting a sheet material, a grip means for gripping the sheet material on the rotary carrier, and a delivery means for delivering the sheet material to the grip means; After driving the sending means, it is temporarily stopped at a predetermined timing,
A sheet material gripping device comprising: a driving means for driving the feeding means again after that; and a control means for controlling the timing according to the position of the sheet material when the feeding means is temporarily stopped. 2) The driving means has a function of controlling the feeding speed of the sheet material of the feeding means to at least a first speed faster than the circumferential speed of the rotary carrier and a second speed slower than the first speed, and the control means , a plurality of sheet material detection means disposed between the delivery means and the gripping position, and a reference signal generation means for generating a signal synchronized with the gripping possible time and the gripping end time of the gripper, and the If the detection means on the upstream side in the feeding direction does not detect the sheet material at the time of the first stop, the primary feeding time from the feeding reference time of the feeding means until the sheet material is temporarily stopped during feeding is determined as the next gripping time. When the detecting means on the downstream side in the feeding direction detects a sheet material, it can be shortened at the next time of gripping, and the signal corresponding to the gripping possible time of the reference signal generating means causes the feeding means to shorten. The variable speed driving means has a function of controlling the speed change drive means so that the sheet material feeding speed of the feeding means is set to a second speed in response to a signal corresponding to the grip end time so that the sheet material feeding speed is set to a first speed. A sheet material gripping device according to claim 1. 3) The control means increases the amount of variation in the primary delivery time if the detection means on the upstream side in the delivery direction does not continuously detect the sheet material for a predetermined number of grip sequences at the time of the temporary stop. , when the detection means on the downstream side in the delivery direction continuously detects the sheet material for a predetermined number of grip sequences, and when the detection means on the upstream side in the delivery direction does not detect the sheet material and on the downstream side in the delivery direction. The sheet material grip according to claim 2, further comprising means for reducing the number of times when the detection means detects the sheet material alternately and consecutively for a predetermined number of grip sequences. Device.