Ink sheet cartridge and recording apparatus utilizing the same

Abstract: There is disclosed an ink sheet cartridge (A) suitable for use in thermal transfer recording (B). The cartridge A has a supply reel (2) and a winding reel (3) for the ink sheet (1), and a guide pin or pins (4e) protruding from the container of the cartridge (A). The guide pins (4e) serve as a guide in cartridge (A) loading, thus facilitating the loading operation and securely determining the cartridge (A) position, thus avoiding eventual disengagement of the reels from the power transmitting gears of the recording apparatus.

Description: The present invention relates to an ink sheet cartridge according to preamble of claim 1, and a recording apparatus utilizing said ink sheet cartridge according to the preamble of claim 2. The recording apparatus includes a printer, an electronic typewriter, a word processor, a copying machine, a facsimile apparatus or the like. In the following description, a facsimile apparatus will be described as an example of the recording apparatus. The facsimile apparatus are now widely used not only in the offices but also in ordinary home. In such facsimile apparatus, for facilitating compactization, there is generally employed so-called thermal recording method utilizing a thermal recording sheet which develops color upon heating. In recent years, however, there have also been developed facsimile apparatus utilizing so-called thermal transfer recording method utilizing an ink sheet. Such facsimile apparatus of the thermal transfer recording method has the advantages of employing an ordinary paper for the recording sheet and of clearer image recording. However, the ink sheet is easily wrinkled because it is very thin. For this reason there has been required a cumbersome operation for loading the ink sheet in the recording apparatus, without causing wrinkles in the ink sheet. It has therefore been proposed to house the ink sheet in a cartridge and load the cartridge in the apparatus or detach it therefrom. However, in loading into the recording apparatus, the cartridge has to be exactly positioned in relation to the recording head and the platen roller of the recording apparatus, and there has inevitably been required a complex positioning mechanism on the ink sheet cartridge. Also the cartridge has to be provided, in a predetermined position thereof, with an aperture for the insertion of the recording head, and the ink sheet is therefore exposed in the aperture. Consequently there result drawbacks of deposition, onto the ink sheet, of dusts entering through the aperture, and eventual damage to thus exposed ink sheet. Furthermore, in the recording operation with the above-explained ink sheet cartridge loaded in the recording apparatus, the driving force has to be transmitted to a take-up reel for winding the advanced ink sheet. For this reason the take-up reel of the detachable cartridge has to be securely coupled with the driving system of the apparatus, and there is thus required a complex structure. The recording operation with the ink sheet cartridge is conducted by passing the ink sheet and a recording sheet between the recording head and the platen roller, and selectively generating heat by the heat generating elements of the recording head thereby transferring the ink from the ink sheet to the recording sheet. In such operation, there may result a lost portion in the transferred image unless the recording head is pressed to the platen roller with a predetermined pressure. On the other hand, in the ink sheet cartridge, the ink sheet is fed from a supply reel to a take-up reel under a certain tension, in order to prevent wrinkle formation in the ink sheet, and the tension may bias the recording head in a direction opposite to the direction of the above-mentioned pressure toward the platen roller. For this reason the pressure between the recording head and the platen roller may fluctuate, thus deteriorating the quantity of image recording. Furthermore, the conventional ink sheet cartridge has been associated with drawbacks of difficulty of ink sheet loading into the cartridge, and difficulty of connection of the ink sheet to the take-up reel in case the ink sheet is eventually broken for some reason. A generic ink sheet cartridge and a recording apparatus are known from the US-A-4 754 290. A projecting guide member at an ink sheet cartridge guides the cartridge when it is loaded into a recording apparatus. The projecting guide member is fixedly connected with the ink sheet cartridge or forms part of it. The winding members are rotatably supported in the ink sheet cartridge and their position is only determined by the ink sheet cartridge itself. Upon loading the position of the winding members remains unchanged. It is an object of the present invention to further develop an ink sheet cartridge according to the preamble of claim 1 and a recording apparatus according to the preamble of claim 2 such that the manufacturing costs are reducible while the winding of winding members is reliably guaranteed. With respect to the ink sheet cartridge this object is achieved by the features indicated in the characterizing portion of claim 1, and with respect to the recording apparatus it is achieved by the features of the characterizing portion of claim 2. Advantageous further developments are set out in the dependent claims. According to the invention the ink sheet cartridge enables an exact positioning in the recording apparatus, in loading into the recording apparatus. The ink sheet cartridge, when loaded in the recording apparatus, can be securely coupled with a driving system of the apparatus thereby receiving the driving force therefrom. Furthermore, the ink sheet cartridge is capable of image recording of high quality. The ink sheet cartridge is capable of being exactly positioned in the recording apparatus with a simple structure and of satisfactory image recording. Fig. 1 is a schematic view of component parts of an ink sheet cartridge; Fig. 2 is a cross-sectional view of a recording apparatus in which the ink sheet cartridge is loaded; Fig. 3 is a perspective view of the ink sheet cartridge with an ink sheet loaded therein; Fig. 4 is a perspective view of a state of adhering the ink sheet to a take-up reel; Figs. 5 and 6 are external perspective views of the ink sheet cartridge; Figs. 7A and 7B are perspective views of a state of loading the ink sheet cartridge into the recording apparatus; Fig. 8 is a block diagram of a control system; Figs. 9A and 9B are cross-sectional views of a state in which the ink sheet cartridge is mounted on positioning members and a recording cover is closed; Figs. 10A and 10B are cross-sectional views showing the relationship between the recording head and a cover member in the loading of the ink sheet cartridge; Figs. 11A and 11B are schematic views showing the relationship between a reel gear and a pendulum gear in closing the recording cover; Fig. 12 is a cross-sectional view in a recording operation; Fig. 13 is a schematic view of an embodiment in which the feeding direction of the ink sheet is reversed; and Figs. 14A, 14B, 15, 16A, 16B, 17A, 17B, 18 and 19 are views of an embodiment in which a U-shaped positioning groove for a reel bearing is provided in the recording apparatus, wherein Figs. 14A and 14B show a state of loading the ink sheet cartridge into the recording apparatus; Figs. 15, 16A and 16B show a state with closed recording cover; Figs. 17A and 17B show the relationship between the recording head and the cover in loading the ink sheet cartridge; Fig. 18 shows a recording state; and Fig. 19 shows an embodiment in which the feeding direction of the ink sheet is reversed. In the following there will be explained an ink sheet cartridge constituting a preferred embodiment of the present invention, and a facsimile apparatus as a recording apparatus utilizing said ink sheet cartridge. [1st embodiment] Fig. 1 is a schematic view showing the structure of an ink sheet cartridge A, and Fig. 2 is a schematic view of a recording apparatus (facsimile apparatus) B in which said ink sheet cartridge A is loaded. In the ink sheet cartridge A, a continuous or elongated ink sheet 1 is wound on a supply reel 2 and a take-up reel 3, which are rotatably accommodated in a container 4. Said ink sheet cartridge A is ao constructed as to be positioned and loaded in a loading part 5 of the recording apparatus B. While said ink sheet 11 and a recording sheet 7 are mutually superposed and are advanced in a recording unit provided with a recording head 6a and a platen roller 6b, the ink of said ink sheet 11 is transferred as an image pattern onto the recording sheet 7. In the following the structure of said ink sheet cartridge A will be explained in greater detail. The ink sheet 1 of the present embodiment has a width corresponding for example to the B4 or A4 size, and is composed of elongated substrate sheet coated thereon with thermal transfer ink (for example heat-fusible or heat-sublimable), wherein said ink is fused, when the substrate sheet is heated, according to the pattern of heating. Said ink sheet 1 itself can be of already known type. Said ink sheet 1 is wound, at an end thereof, on the supply reel 2, and, at the other end, on the take-up reel 3. As shown in Fig. 1, shafts 2a, 3a of said supply reel 2 and take-up reel 3 are provided, at both ends thereof, with flanges 2b 1 , 2b 2 , 3b 1 , 3b 2 , and reel gears 2c, 3c for receiving the driving force are integrally formed on the flanges 2b 1 , 3b 1 . The reel shafts 2a, 3a extend beyond said gears 2c, 3c and flanges 2b 2 , 3b 2 to form end portions 2a 1 , 3a 1 , which are rotatably fitted in bearings 8. Said reels 2, 3 supporting the ink sheet 1 are housed in the container 4. Said bearings 8 are composed of a low friction material such as polyacetal, polyamide, polybutylene terephthalate etc. so that the reel shafts 2a, 3a can smoothly rotate in the bearings 8. In the following there will be explained the structure of said container 4. As shown in Fig. 1, said container 4 is composed of a first casing member 4a and a second casing member 4b, which are mutually linked by unrepresented hinges, so as to be opened or closed. Said first casing member 4a is composed of a base plate 4a 1 with curved ends, and vertical side plates 4a 2 perpendicularly provided at both lateral ends. In predetermined positions of said side plates 4a 2 there are provided two pairs of U-shaped grooves 4c, 4d with a predetermined gap therebetween. In the U-shaped grooves 4c, there are fitted the bearings 8 for the supply reel 2, while in the other grooves 4d there are fitted the bearings 8 for the take-up reel 3, whereby said supply reel 2 and take-up reel 3 are loaded in the first casing member 4a. Guide pins 4e for mounting the ink sheet cartridge A on the recording apparatus B are provided on said side plates 4a 2 , substantially on a line passing through said U-shaped grooves 4c and 4d, at an end close to said hinges. As will be explained later, said guide pins 4e serve as guide members and as rotating centers in loading the ink sheet cartridge A into the recording apparatus B. In the present embodiment, the U-shaped grooves 4c, 4d are made larger than the bearings 8 by about 2 mm in the vertical direction and by about 0.5 mm in the longitudinal direction, in order that said bearings 8 are fitted with a certain play in said grooves. Therefore, in the ink sheet cartridge A of the present embodiment, when the casing members 4a, 4b are mutually closed with the bearings 8 fitted in the U-shaped grooves 4c, 4d, the line connecting the centers of said bearings 8 is positioned about 2 mm above the center of the guide pin 4e. Consequently, in the present embodiment, in loading the ink sheet cartridge A into the recording apparatus B, smooth positioning of the cartridge A is ensured as the bearings 8 almost simultaneously fit into U-shaped grooves 28b, 28c of positioning members 28. Said guide pin 4e is either positioned on the extention of a line connecting the centers of the bearings 8, or positioned within a distance of 10 mm from said extension, preferably 5 mm and most preferably 2.5 mm. Within said distance, the cartridge A can be more smoothly loaded in the recording apparatus. In the present embodiment, as will be explained later, the line connecting the centers of the bearings 8 substantially passes the center of the guide pin 4e when the loading of the cartridge A into the apparatus B is completed. In a predetermined position of said base plate 4a 1 , at approximate center of the U-shaped grooves 4c and 4d, there is provided an aperture 4f for enabling insertion of the recording head 6a when loaded in the recording apparatus B, and said aperture 4f is provided with hinged covers 4g. Each of said covers 4g is rotatably mounted on the base plate 4a 1 by means of hinges 4h, and a torsion coil spring 4i provided at an end of said cover 4g biases said cover 4g toward the outside. In predetermined positions of said base plate 4a 1 , there are provided, as shown in Fig. 6, limiting plates 4j for limiting by the torsion coil spring 4i from biasing the cover 4g in an open direction. Inside said side plates 4a 2 and in the vicinity of the loading position of the take-up reel 3, there are provided upright members 4k 1 , supporting a guide shaft 4k for guiding the movement of the ink sheet 1 as will be explained later. Instead, said guide shaft 4k may be provided on a recording cover 11 of the apparatus. As in the first casing member 4a explained above, the second casing member 4b is composed of a base plate 4b 1 with curved ends and vertical side plates 4b 2 . At the approximate center of said base plate 4b 1 , there is provided an aperture 4ℓ 1 for allowing entry of the platen roller 6b when the cartridge A is loaded in the apparatus B, and said aperture 4ℓ 1 is continued to notches 4ℓ 2 formed in the side plates 4b 2 for accomodating the platen roller shaft. Also in predetermined positions of said base plate 4b 1 , there are formed apertures 4m for exposing the gears 2c, 3c of the supply and take-up reels 2, 3 housed in the container 4. Said gears 2c, 3c exposed in the apertures 4m mesh with a driving gear 31 linked with a motor of the recording apparatus B, whereby the rotating power is transmitted to the reels 2, 3. An engaging projection 4n is provided in a predetermined position at the open end of said second casing member 4b, and the ink sheet cartridges A can be loaded into the recording apparatus B by fitting said engaging projection 4n with an engaging spring of a loading part 5. Outwardly extending grips 4o are formed on the side plates 4b 2 of the second casing member 4b and can be used by the operator for disengaging said projection 4n from the engaging spring, in case of detaching the ink sheet cartridge A from the apparatus B. The first casing member 4a is provided with recessed engaging portions 4p at the open end thereof, while the second casing member 4b is provided with matching engaging projections 4q at the open end thereof, whereby, in the closed state of the casing members 4a, 4b, said recessed engaging portions 4p and the engaging projections 4q mutually engage to maintain the closed state. The ink sheet 1 can be loaded into the container 4 in the follwoing manner. The bearings 8 are fitted on both ends of the supply reel 2 and the take-up reel 3 supporting the ink sheet 1 as shown in Fig. 1, and are fitted in the U-shaped grooves 4c, 4d of the first casing member 4a. The ink sheet 1 is so set that it is wound on the take-up reel 3 from above to below, or clockwise in Fig. 3. In such sheet setting, the front end of the ink sheet 1, when it is eventually broken, can be directly adhered onto the upper part of the take-up reel shaft 3a for example with an adhesive tape 9 as shown in Fig. 4. On the other hand, if the ink sheet is so set that it is wound on the take-up reel 3 anticlockwise, namely from below to above, the front end of the broken ink sheet 1 has to be threaded under the take-up reel 3 before it is adhered to said reel 3. Thus the above-explained setting of the ink sheet 1 in the first casing member 4a facilitates the splicing operation in case of breakage. Also in the present embodiment, the U-shaped grooves 4c, 4d for accommodating the bearings 8 are only provided in the first casing member 4a, so that the ink sheet cannot be set in the second casing member 4b. It is therefore possible to prevent erroneous inverse setting of the ink sheet 1 in the second casing member 4b, for example at maintenance. Nevertheless, said U-shaped grooves may be provided on both first casing member 4a and second casing member 4b. After the supply reel 2 and the take-up reel 3 supporting the ink sheet 1 are set in the first casing member 4a, the second casing member 4b is rotated with respect to the first casing member 4a as shown in Figs. 5 and 6, thereby causing mutual engagement of the engaging portions 4p and engaging projections 4q of the casing members 4a, 4b and maintaining the ink sheet cartridge A in the closed state. The above-explained ink sheet cartridge A can prevent intrusion of dusts through the aperture 4g during storage or transportation, due to the presence of covers 4g in said aperture 4f. Also said covers prevent the ink sheet 1 from eventual damages, and serve to hide the interior thereby giving a high-classed appearance to the cartridge. In the following there will be explained the structure of the recording apparatus B for thermal transfer recording with the ink sheet cartridge A loaded therein. The recording apparatus B of the present embodiment is constructed as a facsimile apparatus equipped with an image reading unit C as shown in Fig. 2. Said apparatus can be opened by rotating a recording cover 11 about a hinge shaft 12 with respect to the main body 10, and said ink sheet cartridge A can be loaded in said recording cover 11. In said main body 10 there are provided a roll holder 13 for drop-in loading of a roll 7a of a continuous recording sheet 7; a platen roller 6b serving as feeding means for feeding said recording sheet 7; a cutter 14 for cutting the recording sheet 7 after recording; and discharge rollers 15 for discharging the sheet 7 after cutting. In the recording cover 11 there is provided, as shown in Figs. 2 and 7A, a line recording head 6a composed of a linear array, across the recording area, of heat generating elements 6a 1 for generating heat according to image signals. When the recording cover 11 is closed, said recording head 6a is pressed against the platen roller 6b by means of the elastic force of a spring 6c, and fork members 6d fixed on both ends of said recording head 6a support the shaft 6b 1 of the platen roller, thereby positioning the recording head 6a with respect to the roller 6b. In the image reading unit C, plural original documents 17 can be stacked on an original stacker 16 formed on the upper face of the recording cover 11. Said plural originals 17 are preliminarily advanced by a preliminary feeding roller 18a and a pressure roller 18b, and are separated and advanced one by one, by means of a separating roller 19a and a pressing member 19b maintained in contact therewith. Said original document 17 is fed by paired transport rollers 20a, 20b for image reading in a reading unit to be explained later, and is discharged onto a tray 21 after said image reading. In the reading unit 60, the original document 17 is illuminated by a light source 22 while it is transported, and the reflected light is guided through mirrors 23 and a lens 24 to a photoelectric converting element 25 such as a CCD. The obtained image signal is supplied to a recording unit of the same apparatus in case of the copy mode, or to the recording unit of another apparatus in case of transmission mode. In Fig. 2, there are also shown a printed circuit board 26, and a power source 27 for driving motors and other components. Fig. 8 is a block diagram showing the control system for controlling the above-explained apparatus. The image reading unit C is provided with a photoelectric converting element 25 explained above, and a motor 56 for driving the preliminary feeding roller 16 and transport rollers 20a, 20b. A line memory 50a in a control unit 50 stores the image data of each line, and serves to store the image data of a line from the image reading unit C in the copying or transmission of the original 17, or the received decoded image data of a line in case of reception of image data. The image recording is conducted by sending the data from said line memory 50a to the recording head 6a. An encoding/decoding unit 50b encodes the image data to be transmitted for example by MH encoding, and decoding the received encoded data into image data. A buffer memory 50c serves to store the encoded image data to be transmitted or data received. These components of the control unit 50 are controlled by a CPU 50d such as a microprocessor. The control unit 50 is further provided with a ROM 50e storing the control program of the CPU 50d and various data, and a RAM 50f for temporarily storing various data as a work area of the CPU 50d. A recording unit 51 is provided with the aforementioned recording head 6a and motors (reel driving motor 32 and platen motor 37) to be explained later, which are driven by signals from the CPU 50d. There are also provided an operation unit 52 including various function keys such as a transmission start key and input keys for telephone numbers; and an indication unit 53 for displaying status of various functions of said operation unit 52 and of the apparatus. There are futher provided a modem 54; and a network control unit (NCU) 55. In the following explained is the structure of the loading unit 5 for loading the ink sheet cartridge A. On both sides of the recording cover 11, as shown in Fig. 7A, there are symmetrically mounted positioning members 28, each of which is provided with a hooked groove 28a for engaging with the guide pin 4e of the ink sheet cartridge A, and U-shaped grooves 28b, 28c for engaging with the bearings 8 supporting the ends of the reels 2, 3 thereby defining the positions of said bearings 8, with predetermined spaces therebetween along a line. Also at the open end of said recording cover 11 there is provided an engaging spring 29 for engaging with the projection 4n of the ink sheet cartridge A. Thus, in loading the ink sheet cartridge A into the cover 11 of the apparatus, the guide pin 4e of said cartridge A is moved along a sloped portion 28a 1 of the hooked groove 28a until it engages with a groove portion 28a 2 as shown in Fig. 7A. The cartridge A can be loaded in the recording cover 11 by then rotating said cartridge A about the guide pin 4e fitted in said hooked groove 28a until the engaging projection 4n engages with the spring 29. In this state the bearings 8 respectively fit into the U-shaped grooves 28b, 28c. When the loading is completed, the center of the guide pin 4e of the ink sheet cartridge A and the centers of the bearings 8 fitted in the U-shaped grooves 4c, 4d substantially lie on a line (dotted line ℓ in Fig. 7B or 19B, so that, when the cartridge A is rotated about the guide pin 4e, the bearings 8 of the supply reel 2 and the take-up reel 3 are substantially simultaneously fitted in the U-shaped grooves 28b, 28c of the positioning member 28. Consequently the bearings 8 can be securely positioned in the U-shaped grooves 28b, 28c, without either one fitting fitted in the groove at first and functioning as the center of rotation. Also in the present embodiment, said guide pin 4e and the U-shaped grooves 4c, 4d for accommodating the bearings 8 are all provided on the first casing member 4a, and the center of said pin 4e and the centers of arcs of the grooves 4c, 4d are positioned substantially along a line, though they are not completely aligned linearly as the bearings 8 are fitted in said U-shaped grooves 4c, 4d with a play of 2 - 3mm. Thus the bearings 8 can be exactly positioned with respect to the guide pin 4e, by substantially linearly arranging the center of arc of the groove 28a 2 of the hooked groove 28a and the centers of arcs of the U-shaped grooves 28b, 28c to be formed on the positioning member 28. Stated differently, the bearings 8 can be positioned with a high precision, by a simple structure of arranging the hooked groove 28a and the U-shaped grooves 28b, 28c substantially linearly on the same positioning member 28. As shown in Fig. 9A, the positioning member 28 of the present embodiment is tapered in thickness in such a manner that the distance between the internal faces 28d is wider in the lower position and becomes narrower at the upper position. Thus said ink sheet cartridge A, when rotated about the guide pin 4e, is guided along said tapering, so that the loading is facilitated and the cartridge A can be maintained without play in the direction of reel shaft (direction Y in Fig. 7B) after loading. Also at the loading of the ink sheet cartridge A explained above, a fork member 6d mounted on the recording head 6a pushes open the covers 4g of the cartridge A against the force of the torsion coil springs 4i as shown in Figs. 10A and 10B, whereby the recording head 6a enters the interior of the cartridge A through the aperture 4f thereof. Since said aperture 4f is provided at the approximate center between the reels 2 and 3, the covers 4g opened by the fork member 6d of the recording head 6a can be of a simple planar structure without touching the ink sheet 1 wound on the reels 2, 3, so that the freedom in designing is increased. It is also possible to compactize the ink sheet cartridge by designing the aperture 4f, substantially determined by the recording head 6a and the fork member 6d so as to satisfy various conditions, and still reducing the space between the reels 2 and 3 and minimizing the unnecessary spaces between the recording head 6a and the reels 2, 3. Since the guide pin 4e is provided at the end of the cartridge A and is separated by a certain distance from the aperture 4f, said aperture 4f can be made as a minimum necessary size for inserting the recording head 6a. The biasing force of the torsion coil springs 4i for returning the covers 4g is selected at a level not affecting the contact pressure of the recording head 6a on the platen roller 6b when said head 6a is inserted as shown in Fig. 10B. In the present embodiment, therefore, the contact pressure between the recording head 6a and the platen roller 6d by the spring 6c is selected approximately at 150 gf/cm, while the biasing force of said torsion coil springs 4i on the covers 4g is selected approximately at 60 gf/cm. The loading of the ink sheet cartridge A can be easily done, as the recording head 6a automatically opens the covers 4g and is inserted into the cartridge A at said loading. Also since the covers 4g are opened to both sides by the pressure of the recording head 6a, there is required a small rotating radius for each cover, and the length of the cartridge A can therefore be reduced. After the ink sheet cartridge A is loaded in the recording cover 11 as shown in Fig. 7B, said cover 11 is closed and latched with the main body 10 by mutual engagement of a hook 30a thereof with a hook 30b of the recording cover. In this state, the reel gears 2c, 3c integrally formed with the reels 2, 3 mesh with driving gears 31 provided in the main body 10. In the main body 10 of the recording apparatus B there are provided reel driving motors 32 as shown in Fig. 7B, and the driving force thereof is transmitted through gears 33a - 33e to the driving gears 31. Said gear 33e is mounted on an arm 34 rotatable about the gear shaft 34a of the gear 33d and constitutes so-called pendulum gear, capable of swinging around said gear 33d while meshing with the same. The driving gear 31 can move integrally with said pendulum gear 33e and receives the rotating force of said gear 33d through a slip clutch 35. Tension springs 36 are provided for pulling the arms 34 upwards. There is also provided a platen motor 37 for rotating the platen roller 6b through gears 38a - 38c. When the recording cover 11 is closed in the above-explained structure, the reel gears 2c, 3c exposed in the apertures 4m of the ink sheet cartridge A mesh with the driving gears 31. In the present embodiment, said apertures 4m are positioned, as shown in Figs. 11A and 11B, on rotating trajectories of the reel gears 2c, 3c about the hinge shaft 12 of the recording cover 11, and said driving gears 31 are also positioned on said trajectories. Consequently, when the recording cover 11 is closed, the gears 2c, 3c exposed in said apertures 4m press the driving gears 31, thus securely meshing therewith. In this state, even if the mother gears 33d linked to the motors 32 are in locked state, the recording cover 11 can be smoothly closed since the pendulum gears 33e integrally moving with the driving gears 31 can smoothly swing around the mother gears 33d. In the main body 10, as shown in Fig. 7B, there are provided plate springs 39 in positions opposed to the bearings 8 of the cartridge A, which is loaded in the recording cover 11, whereby said bearings 8 are pressed toward the U-shaped grooves 28b, 28c of the positioning members 28 by means of said plate springs 39. Thus, as shown in Fig. 9B, the bears 8 are securely positioned in the direction of height (direction Z in Fig. 7B). Said plate springs 39 are positioned corresponding to the U-shaped grooves 28b, 28c across the reel shaft, as shown in Fig. 9B, since otherwise the bearings 8 is subjected to torsion, causing unnecessary friction in the rotation of the reels 2, 3. The bearings 8 are thus positioned in the U-shaped grooves 28b, 28c of the positioning members 28, independently from the positioning of the ink sheet cartridge A in the recording cover 11. Stated differently, the direct positioning of said bearings 8 on the recording apparatus without through the cartridge A allows to improve the precision, for example of parallel arrangement between the reels 2, 3 and the platen roller 6b. Rigidity or precision is not required for the cartridge A itself, as the positional precision of the bearings 8 is not achieved by said cartridge A. For this reason the cartridge A can be manufactured inexpensively. In the present embodiment, when the recording cover 11 is closed, the contact position between the recording head 6a and the platen roller 6b is located at approximate center of the cartridge A in the direction of height, as shown in Fig. 10B. If said contact position is located higher in the cartridge A, the recesses 4ℓ 2 shown in Fig. 1 for accommodating the shaft of the platen roller 6b have to be made deeper, so that the second casing member 4b becomes mechanically weaker. On the other hand, if said contact position is lower in the ink sheet cartridge A, the aperture 4f has to be made larger for accepting the recording head 6a. However, in the present embodiment, said contact position is approximately located at the center so that the aperture 4f can be minimized in size without sacrificing the strength of the second casing member 4b. In the following there will be explained the recording operation of the recording apparatus B in which the ink sheet cartridge A is loaded. In the recording operation, the platen motor 37 and the reel driving motor 32 of the take-up reel are driven while the motor 32 of the supply reel is locked. By the activation of said platen motor 37, the platen roller 6b is rotated in a direction a in Fig. 12, thereby advancing the recording sheet 7 and the superposed ink sheet 1 respectively in directions b , c . In synchronization, the heat generating elements 6a 1 of the recording head 6a are energized according to the image signals to heat the ink sheet 1 imagewise, thereby transferring the fused ink to the recording sheet 7. In said recording operation, the reel driving motor 32 for the take-up reel 3 drives the reel 3 with a peripheral speed slightly larger than that of the platen roller 6b in order to avoid the slack in the ink sheet 1 advanced by said platen roller 6b, and the speed difference is absorbed by the slip clutch 35. Thus the ink sheet 1 is taken up on the reel 3 under a front tension. On the other hand, since the reel driving motor 32 for the supply reel 2 is locked, the supply reel 2 is subjected to the slipping load of the slip clutch 35, and rotates according to the advancement of the ink sheet 1, thereby giving a back tension thereto. Referring to Fig. 12, if the front tension of the ink sheet 1 in winding on the take-up reel 3 is strong enough to push the recording head 6a upwards, the pressure thereof on the platen roller 6b may fluctuate, eventually resulting in failure in the image transfer. In the present embodiment, however, since the ink sheet 1 after recording is guided, by the guide shaft 4k positioned lower than the recording position R between the head 6a and the platen roller 6b, downwards from said position R, so that the recording head 6a is not pushed upwards by the ink sheet 1 even if the front tension thereof is strong. Consequently the recording head 6a applies a constant pressure on the platen roller 6b, without the fear of failure in image transfer. As already explained before, said guide shaft 4k may be provided either in the ink sheet cartridge A or in the recording cover 11. Also as shown in Fig. 12, the reel gear 2c of the supply reel 2 is biased upwards by the idling rotation of the driving gear 31 subjected to the slip load, but the bearings 8 do not move upwards as they are supported by the U-shaped grooves 28b, 28c from above. Thus, since the U-shaped grooves 28b, 28c are formed in such a direction as to limit the movement of the reel gears 2c, 3c biased by the driving gears 31, the reel gears 2c, 3c are prevented from such movement and from disengagement from the driving gears 31. In the following there will be explained the replacement of the ink sheet cartridge A or the detachment thereof from the recording cover 11. For this purpose, the recording cover 11 is opened as shown in Fig. 7B, and the cartridge A is pulled toward front by the grips 4o, whereby the projection 4n of the cartridge A is disengaged from the spring 29. Thus the cartridge A rotates about the guide pins 4e as shown in Fig. 7A and can be easily detached from the recording cover 11. Since the grips 4o and the engaging projection 4n are both provided on the second casing member 4b, the pulling action on said grips 4o does not apply any force on the engagement between the recesses 4p of the first casing member 4a and the projections 4q of the second casing member 4b. This fact presents undesired opening of the first and second casing members 4a, 4b in the disengagement of the projection 4n from the spring 29. As detailedly explained in the foregoing, the ink sheet cartridge A of the present embodiment can be easily loaded, with sufficient positional precision, into the recording apparatus B equipped with the recording head 6a, and ensures recording of high image quality, by securely avoiding the slippage or disengagement of gears in the transmission system. [Another embodiment] In the foregoing first embodiment, the ink sheet 1 is advanced in the same direction as the recording sheet 7 in the recording operation, but it is also possible, as shown in Fig. 13, to feed the ink sheet 1 in a direction d opposite to the feeding direction b of the recording sheet 7. In such case, the structure of the ink sheet cartridge A is same as that in the foregoing first embodiment, except that the supply reel 2 and the take-up reel 3 are inverted. In this structure, the reel gear 3c of the take-up reel 3 is linked to the driving motor through the gears but without the slip clutch. In the recording operation with this structure, the recording sheet 7 is advanced in a direction b by the platen roller 6b while the ink sheet 1 is advanced in a direction d by the reel driving motor of the take-up reel. The gears coupled with the reel gear 2c of the supply reel 2 are provided with a slip clutch 35, whereby the reel 2 is subjected to a slip load, thus a back tension to the ink sheet 1. Also in the foregoing first embodiment, the U-shaped grooves 28b, 28c for positioning the bearings 8 are provided in the recording cover 11, but they may be provided in the main body 10. Such embodiment will be explained in the following with reference to Figs. 14A, 14B, 15, 16A, 16B, 17A, 17B and 18, wherein same components as those in the foregoing embodiment are represented by same numbers and will not be explained further. Figs. 14A and 14B show a state of cartridge loading into the recording apparatus, corresponding to Figs. 7A and 7B; Figs 15, 16A and 16B shows a state with closed recording cover, corresponding to Figs. 9A and 9B; Figs. 17A and 17B show the relationship between the recording head and the cover corresponding to Figs. 10A and 10B; Fig. 18 shows a recording state corresponding to Fig. 12; and Fig. 19 shows a schematic view of an embodiment in which the feeding direction of the ink sheet is reversed, corresponding to Fig. 19. As shown in Figs. 14A, 14B, 16A and 17A, U-shaped grooves 40a, 40b for positioning the bearings 8 of the supply reel 2 and take-up reel 3 are provided in predetermined positions of the main body 10, while positioning members 41 only having the hooked grooves 28a for positioning the guide pins 4e of the ink sheet cartridge A are provided on the recording cover 11. Also on said cover there is provided the spring 29 for engaging with the projection 4n of the cartridge A. Consequently the cartridge A can be loaded in the recording cover 11 as in the foregoing embodiment, by fitting the guide pins 4e into the hooked grooves 28a and engaging the projection 4n with the spring 29. Then the recording cover 11 is closed, whereby, as shown in Figs. 15, 16B and 17B, the bearings 8 are fitted and positioned in the U-shaped grooves 40a, 40b provided in the main body 10. As shown in Fig. 15, springs 42 are provided in said U-shaped grooves 40a, 40b for maintaining the upper ends of the bearings 8 in contact with contact portions 41a, 41b of the positioning members 41 when the recording cover 11 is closed. By forming the positioning means for the bearings 8 in the main body 10 on which the platen roller 6b is mounted, it is easily possible to achieve a highly precise parallel relationship between the platen roller 6b and the reels 2, 3 positioned by said U-shaped grooves 40a, 40b. Also, even if the reel gears 2c, 3c are pushed upwards in Fig. 15 by the driving gears 31 as in the first embodiment, the disengagement of gears does not occur since the bearings 8 are prevented from movement in the vertical direction, in contact with the contact portions 41a and 41b. Also in the foregoing embodiment, it is possible to feed the ink sheet 1 in a direction d opposite to the feeding direction b of the recording sheet 7 as shown in Fig. 19. As detailedly explained in the foregoing, the present invention provides an ink sheet cartridge capable of image recording of high quality, and a recording apparatus utilizing said ink sheet cartridge. There is disclosed an ink sheet cartridge suitable for use in thermal transfer recording. The cartridge has a supply reel and a winding reel for the ink sheet, and a guide pin or pins protruding from the container of the cartridge. The guide pins serve as a guide in cartridge loading, thus facilitating the loading operation and securely determining the cartridge position, thus avoiding eventual disengagement of the reels from the power transmitting gears of the recording apparatus.

Claims: An ink sheet cartridge loadable on a recording apparatus, comprising: a first winding member (2) capable of winding the ink sheet (1) thereon, a second winding member (3) capable of winding the ink sheet (1) thereon, a frame member (4) for supporting said first and second winding members (2, 3) and a projecting guide member (4e) projecting outwardly from said frame member (4) serving as a guide in the loading of the cartridge into the recording apparatus, characterized by a positioning member (8) for defining the positions of said first and second winding members (2, 3) with respect to the recording apparatus in the loading of said cartridge therein; and an engaging member (4n) for engaging said frame member (4) with the recording apparatus in the loading of said frame member (4) thereinto. A recording apparatus for image recording on a recording medium (7), comprising: a loading unit (10) capable of loading therein an ink sheet cartridge (A) including a first winding member (2) capable of winding an ink sheet (1) thereon, a second winding member (3) capable of winding said ink sheet (1) thereon, a frame member (4) for supporting said first and second winding members (2, 3) and a projecting guide member (4e) projecting outwardly from said frame member (4) serving as a guide in the loading of the cartridge into the recording apparatus, recording means (6a) for acting on said ink sheet (1) contained in said ink sheet cartridge (A) loaded in said loading unit (10) for image recording on said recording medium (7) and feeding means (6b, 15) for feeding said recording medium (7), characterized by a positioning member (8) provided on said cartridge (A) for defining the positions of said first and second winding members (2, 3) with respect to the recording apparatus in the loading of said cartridge (A) therein; and an engaging member (4n) provided on said cartridge (A), for engaging said frame member (4) with the recording apparatus in the loading of said frame member (4) thereinto; positioning means (28b, 28c) for defining the position of said positioning member (8) provided on said ink sheet cartridge (A); and engaging means (29) for engaging with said engaging member (4n). An ink sheet cartridge according to claim 1, characterized in that said positioning member (8) is a bearing (8) or an ink sheet reel. An ink sheet cartridge according to claim 1 or 3, characterized in that said engaging member (4n) is an engaging projection (4n). An ink sheet cartridge according to claim 1, 3 or 4, characterized in that said first winding member (2) consists of a supply reel (2) for supplying said ink sheet (1), said second winding member (3) consists of a winding reel (3) for winding said ink sheet (1), and said frame member (4) comprises a container (4) for supporting said supply reel (2) and said winding reel (3). An ink sheet cartridge according to claim 5, characterized in that said container (4) is composed of mutually openable first and second casing members (4a, 4b), wherein grooves (4c, 4d) for fitting said supply reel (2) and winding reel (3) are formed in said first and/or second casing member (4a, 4b) of the container (4). An ink sheet cartridge according to claim 5 or 6, characterized in that said projecting guide member (4e) is provided at an end portion on a lateral face or faces of said container (4). An ink sheet cartridge according to any of the claims 1 or 3 to 7, characterized in that the position substantially on the extension of the line connecting the axes is a position not distanced in excess of 10 mm, preferably 5mm, and most preferably 2.5 mm from said extension of the line. An ink sheet cartridge according to any of claims 5,6 or 7, characterized in that bearings (8) are rotatably mounted on said supply reel (2) and on said winding reel (3) and said container (4) supports said bearings (8). An ink sheet cartridge according to any of claims 5,6,7 or 9, characterized by an ink sheet guide member (4k) for guiding said ink sheet (1) in such a manner that the tension of said ink sheet (1) supplied from said supply reel (2) and wound on said winding reel (3) does not apply a biasing force on a recording head (6) provided in said recording apparatus. An ink sheet cartridge according to any of claims 5,6,7,9 or 10, characterized by reel gears (2c, 3c) respectively provided on said supply reel (2) and said winding reel (3), wherein said container (4) is provided with apertures (4m) for exposing said reel gears (2c, 3c). An ink sheet cartridge according to claim 1 or 3 to 11, charaterized in that said projecting guide member (4e) projects outwardly from said frame member in a position close to the extension of a line connecting the axis of said first and second winding members (2, 3). A recording apparatus according to claim 2, characterized in that said ink sheet cartridge (A) includes a supply reel (2) as first winding member for supplying said ink sheet (1) and a winding reel (3) as second winding member for winding said ink sheet (1), said recording means (6a) heats said ink sheet (1) contained in said ink sheet cartridge (A) according to image signals; wherein said engaging means (29) for defining the loaded position of said ink sheet cartridge (A) is independent from positioning means (28b, 28c) for defining the positions of said supply reel (2) and said winding reel (3). A recording apparatus according to claim 13, characterized by a main body (10) and a recording cover (11) which can he opened or closed with respect to said main body (10), wherein said positioning means (28b, 28c) for defining the positions of said supply reel (2) and said winding reel (3) is provided in said recording cover (11). A recording apparatus according to claim 14, characterized in that said main body (10) is provided with a contact portion (31, 33e) for contacting with said supply reel (2) and said winding reel (3). A recording apparatus according to any of claims 13 or 14, characterized in that bearings (8) are rotatably mounted on said supply reel (2) and said winding reel (3) and adapted to be positioned by said positioning means (28b, 28c) of the recording apparatus, wherein bearings (8) are supported by said frame member (4). A recording apparatus according to claim 2, characterized by tension means (32, 35) for applying a tension to said ink sheet (1) supplied from said first winding member (2) and wound on said second winding member (3), and by a guide member (4k) for guiding said ink sheet (1) in such a manner that the tension of said ink sheet (1) does not affect said recording means (6a). A recording apparatus according to claim 2, characterized in that driving force receiving members (2c, 3c) are respectively provided on said first and second winding members (2, 3) for receiving the driving force; and transmission means (31, 33e) for transmitting the driving force to said driving force receiving members (2c, 3c) are provided swingably along the arcs of rotary trajectories of said driving force receiving member (2c, 3c) at the closing operation of the main body (10) of the recording apparatus. A recording apparatus according to claim 18, characterized in that said first and second winding members (2, 3) and said driving force receiving member (2c, 3c) thereof are provided in a cover (11) which can be opened or closed with respect to a main body (10) of the apparatus equipped with said transmission means (31, 33e). A recording apparatus according to claim 2 or 12 to 19, characterized in that said projecting guide member (4e) projects outwardly from said frame member in a position close to the extension of a line connecting the axis of said first and second winding members (2, 3).

Inventors: AWAI TAKASHI, ISHIDA YASUSHI, TOMODA AKIHIRO, YOKOYAMA MINORU, AWAI, TAKASHI, ISHIDA, YASUSHI, TOMODA, AKIHIRO, YOKOYAMA, MINORU
Applicants: CANON KK, CANON KABUSHIKI KAISHA
Application year: 1990
Main classification: B41J17
IPC codes: B41J17