JPH066387B2 - Printers and hammer banks for printers - Google Patents

Description

The present invention relates to an impact printer, and more particularly to a dot matrix line printer. This dot-matrix line printer is driven so that an elongated hammerbank reciprocates relative to a print paper of a predetermined width, and at the same time, a hammerbank combined with a hammerspring is provided in the longitudinal direction of the hammerbank. A plurality of magnet type hammer actuators placed along
Selectively actuated to release the hammer spring,
As a result, dots are printed on the print paper.

[Prior Art] A printer is known in which an elongated hammerbank is reciprocally moved relative to a printing paper in both directions to perform impact printing of dots. One example of such a printer is U.S. Pat. No. 3,941,051 issued Mar. 2, 1976 (Barrus et al., PRINTER SYS.
TEM), which is assigned to the assignee of the present patent application.

The Barrus et al. U.S. patent describes a dot matrix line printer with an elongated hammerbank that is reciprocally driven by a cam drive mechanism. A ribbon deck mounted inside the printer close to the hammer bank causes a plurality of hammer springs to be mounted in parallel on the hammer bank at intervals in the longitudinal direction thereof, and a platen close to the hammer springs. An ink ribbon is arranged between the and. The printing paper having a predetermined width arranged between the ink ribbon and the platen is stepped by the paper feeding unit driving mechanism so as to pass through the printing area (printing station) defined by the space between the hammerbank and the platen. Be moved.

The printer described in the aforementioned US patent of Barrus et al. Prints in a dot matrix manner. When the hammer bank is reciprocated back and forth on the print paper, some of the plurality of hammer springs mounted along the length direction on the hammer bank,
The spring is released from the retracted position, which is the flexed position, that is, fired. The hammer spring is always held in this retracted position by a magnet type hammer actuator associated with it. When each hammer spring is released or fired, the upper end, which is the free end of the hammer spring carrying the dot impact print tip, pops out from the retracted position to the front, resulting in the dot impact print tip A single dot is printed by hitting the ribbon on the print paper. The hammer spring that bounced back returns to the retracted position. Each magnet type hammer actuator includes a permanent magnet, and this permanent magnet is attracted and connected via a pole piece to an upper end which is a free end of a hammer spring combined with the magnet type hammer actuator. This permanent magnet always stores the hammer spring in the retracted position, which is the bending position of the spring, in a state where it can be opened, that is, fired. The magnet type hammer actuator further includes a magnetic coil surrounding the pole pieces, and the magnetic coil is momentarily excited to act so as to cancel the influence of the permanent magnet, whereby the hammer spring is released to be printed on the printing paper. Dots are printed.

[Problems to be Solved by the Invention] US Patent No. 39410 of Barrus et al. Mentioned above.
In a hammer bank of the type described in No. 51, a plurality of hammer springs are repeatedly opened or fired at high speed when the hammer bank reciprocates back and forth in the width direction of the printing paper. The magnetic coils are repeatedly excited, so that they rapidly become hot. Therefore, provision is needed to cool those coils. One configuration for cooling the coil is 197
U.S. Pat. No. 4,033,255 dated Jul. 5, 1995 (Kl
eist et al., PRINT HAMMER ACTUATOR FOR DOT MATRIX P
RINTERS), which is assigned to the assignee of the present patent application. The arrangement described in the Kleist et al. U.S. patent uses cooling fins mounted on top of the magnetic coil. The cooling fins absorb heat from the magnetic coils and then easily dissipate this heat into the air flowing around the fins, which is pressurized and blown onto the fins. Another arrangement for cooling the coil is US Pat. No. 4,044,668 (Barrus et al., PRINT HAMMER MECHA) dated Aug. 30, 1977.
NISM), which is assigned to the assignee of the present patent application. The fourth of this Barrus et al.
In the arrangement of the 044668 patent, pressurized air is guided behind the hammerbank, from which it passes through an opening formed in the rear wall of the hammerbank as well as the open ends of the hammerbank. It flows into the hammer bank. The air inside the hammerbank flows upwards, around the magnetic coil, and then out through the filter-equipped outlet to the outside of the printer.

These US patents of Kleist et al., As well as Barrus et
Although the magnetic coil cooling structure described in the US Pat. No. 4,044,668 patent can provide effective coil cooling in many cases, these cooling methods are used for a hammer bank of a certain shape. Has limited suitability.
This is especially true for the more recent hammerbank constructions, i.e. the requirement for printing speed has recently made it necessary to incorporate a large number of hammersprings inside a hammerbank of a given size. It has been done. For magnetic hammer actuators, the design can also be modified to accommodate more and, for example, more closely packed hammer springs with smaller dimensions. The high speed hammerbank thus made is not suitable for cooling, for example by using fins mounted on a coil or by a structure in which air simply passes inside the hammerbank. Can not.

In a hammerbank of the type described in the above-noted Barrus et al. Patent No. 3941051, adjacent magnetic hammer actuators are in close physical proximity to each other and, in some cases, in some cases. Since adjacent magnet type hammer actuators share a common member, there is some magnetic interaction between adjacent magnet type hammer actuators. Some magnetic interaction is acceptable, especially when performance requirements are not demanding. However, if the printing speed is higher, and especially if the magnetic hammer actuators have to be arranged more closely together to accommodate more hammer springs, the magnetic interaction causes The problem to be addressed becomes more serious.

Various techniques have been used to reduce the effects of magnetic interactions between adjacent magnet hammer actuators. One of those techniques is 1981 7
US Patent Publication No. 4280404 (Ba
rrus et al., PRINTER HAVING VARIABLE HAMMER RELEASE
DRIVE), which is assigned to the assignee of the present patent application. The technique of this US patent is
The current applied to the coil is changed according to the number of hammers that are going to be fired at one time. Yet another technique is US Pat. No. 438, June 7, 1983.
No. 6563 (Farb.PRINTING SYSTEM HAVING STAGGERED
HAMMER RELEASE), which is assigned to the assignee of the present patent application. In the technique of this U.S. Patent, multiple hammer springs used alternately are fired at different times in the firing cycle so that adjacent hammer springs are not fired at the same time. Although the alternating hammering techniques described in these patents have been effective in reducing the effects of magnetic interactions in many applications, the need to use such techniques It would be advantageous to eliminate the additional equipment and operational complexity associated with using such techniques. Ideally, the firing timing of the hammer should be independent of the considerations for these techniques so that the spacing of the dots on the print paper can be changed infinitely.

Most hammerbanks of the type described in the aforementioned Barrus et al. U.S. Pat. The shaft is slidably mounted inside the bearing to reciprocate the hammer bank. Typically, the shafts are formed as solid shafts and are attached to both ends of the hammerbank with, for example, an adhesive. Despite considerable care being taken in bonding the shafts to the ends of the hammerbank, they are not always exactly coaxial with the common longitudinal axis of the hammerbank. Moreover, the strength of the connection between the shaft and the hammerbank thus connected is sometimes only inadequate. Therefore, there is room for improvement in the structure of the mounting shaft in this type of hammerbank.

In a hammerbank of the type described in the aforementioned Barrus et al. U.S. Pat. The lower ends of these hammer springs are fixed to a hammer mounting surface extending along the longitudinal direction of the hammer bank. As a typical example, each hammer spring is fixed to this hammer mounting surface by a relatively short screw, and this screw penetrates the mounting plate and the lower end of the hammer spring to allow the hammer spring to be mounted. It is screwed into a hole that extends from the surface toward the inside of the hammerbank. Due to hammerbank design considerations, this threaded hole has, for example, a limited length, and therefore relatively short screws must be used to mount the hammerspring. Often, after mounting the screw, dust and foreign matter such as oil from surrounding members may accumulate between the tip of the screw and the bottom of the screw hole. A more desirable hammerbank configuration would be one that would not significantly limit the dimensions of the hammerspring mounting screws and would not trap foreign matter inside the screw holes.

In a hammerbank of the type described in the aforementioned Barrus et al. U.S. Pat. No. 3,941,051, a cover assembly is provided on the hammerbank, with the hammerbank and a sheet support platen disposed adjacent thereto. It is placed on the boundary surface between them. The ink ribbon from the ribbon deck is inserted inside the cover assembly, and the cover assembly holds the ink ribbon between the dot print impact chip formed on the hammer spring and the print paper supported by the platen. There is. When the individual hammer springs are fired, the dot print impact tips project through openings formed in the cover assembly, which allows a small portion of the ink ribbon to strike the print paper. The lower edge of the cover assembly is secured to the lower portion of the hammerbank near the lower end, which is the mounting end of the hammer spring, by suitable fastening means such as screws. The upper edge of the cover assembly, which is opposite the lower edge, is fixed in a suitable manner while being fixed relative to the hammerbank.

In the particular hammerbank described in the aforementioned US Pat. No. 3,941,051 to Barrus et al., The magnetic flux of the individual permanent magnets of the magnet type hammer actuator causes the magnetic flux of substantially the entire hammerbank structure to be carried. ing. The upper edge of the cover assembly is conveniently attached to a fixed datum provided in the upper portion of the hammerbank utilizing the magnetic attraction that exists across the entire hammerbank. is there. However, in hammerbank constructions where the magnetic field lines are contained within a very small area and do not exist over a large portion of the hammerbank, the top edge of the cover assembly is Another means of anchoring in the bank must be adopted.

Therefore, an improved air cooling system for the hammerbank is provided, which eliminates the need to attach heat radiation fins to the magnetic coil and optimizes the cooling action of the pressurized air flowing inside the narrow space inside the hammerbank. It is desirable to do. Furthermore, the magnetic interaction between the densely arranged magnet type hammer actuators is reduced so that the firing operation of each hammer spring can be performed independently of the firing operation of the other hammer springs. ,
Moreover, it would be advantageous to provide a hammerbank that does not require the use of techniques for compensating for magnetic interactions, such as varying coil current or alternating firing timing. . Further, it would be advantageous if separate shafts were not required to be attached at both ends of the hammerbank in order to mount the hammerbank reciprocally. Further, it would be advantageous to provide a hammer bank that allows the use of longer hammer spring mounting screws and does not collect foreign material at the bottom of the screw holes. Furthermore, if the permanent magnet of the magnet type hammer actuator magnetizes only a part of the hammer bank, which is not substantially the whole, another stop for fixing the upper edge of the cover assembly to the hammer bank. Advantages may be obtained by providing a dressing structure. Furthermore, by providing a hammer bank in which a part of the members forming the magnet type hammer actuator is formed in a shape that promotes containment of cooling air and flow of the cooling air around the magnetic coil. , Get the benefits.

[Means for Achieving the Object] The above-described object of the present invention is achieved by providing an improved hammerbank structure having features for overcoming many of the problems of conventional hammerbanks. .

The hammerbank according to the invention employs an improved air-cooling system, in which pressurized air is introduced into a common high-pressure chamber, the common high-pressure chamber being a shuttle in which the hammerbank is arranged. It is formed at the bottom of an elongated cavity located inside the base. The hammerbank is provided with a structure consisting of openings spaced apart from one another in the longitudinal direction of the hammerbank. A first high pressure chamber is formed below the magnetic coil in a region between the hammer spring and the hammer bank, and the opening allows air to flow from the common high pressure chamber to the first high pressure chamber in a turbulent state. Moreover, it is introduced into the first high pressure chamber at a high speed. As a result, an enhanced cooling action is obtained inside the narrow space of the first high-pressure chamber, and in the state where there are many magnetic coils to be cooled.

In the hammer bank having the preferred structure according to the present invention, the plurality of openings extending from the common high pressure chamber through the hammer bank include a first plurality of openings and a second plurality of openings.
The first plurality of openings extend substantially vertically between the bottom of the hammerbank and the first high pressure chamber. Each opening of the second plurality of openings extends substantially horizontally between the back surface of the hammer bank located in the upper portion of the common high pressure chamber and the first high pressure chamber.
Each opening of the second plurality of openings has a second inside of the hammerbank.
It extends through an elongated cavity forming a high pressure chamber. Furthermore, the first plurality of openings and the second plurality of openings are arranged in a zigzag pattern along the longitudinal direction of the hammerbank. Such a structure increases the velocity of the air inside the first high pressure chamber and causes a considerable turbulence in the air, thereby optimizing the cooling action of the magnetic coil at the upper end of the first high pressure chamber. Has been done.

According to one particular feature of the improved air cooling system of the present invention, the magnetic coil is mounted on a bobbin having a large flange, the flange being at the outer end of the bobbin.
It is located close to the movable part of the upper end of the hammer spring. The flanges of each bobbin closely extend side by side with each other, thereby forming an air dam. This air dam prevents, for most of the air, turbulent high-velocity air in the first high-pressure chamber from leaking laterally through the gap between the adjacent hammer springs. Since leakage is prevented,
The air is generally confined within the first high pressure chamber and flows there upwards and around the magnetic coil, thereby providing the desired cooling effect.

In the improved hammerbank of the present invention, the magnetic interaction between adjacent magnet type hammer actuators is reduced by employing magnetic circuits that are essentially independent of each other, and the magnetic circuits are Are not connected by a common magnetic member with one exception. Each magnet type hammer actuator comprises a pair of pole pieces, which are provided with a permanent magnet between them in the vicinity of their rear part and with a magnetic coil mounted on their front part. The pair of magnetic pole pieces and the permanent magnet sandwiched between the pair of magnetic pole pieces are mounted inside a groove formed in a common portion made of aluminum or other non-magnetic material forming a part of the hammerbank. It is placed. The magnetic circuit of each magnet-type hammer actuator obtained as a result of the above-described configuration has a permanent magnet, a pair of magnetic pole pieces including a magnetic coil provided therein, and an extension between the magnetic pole pieces of the pair of magnetic pole pieces. It is enclosed within a small area enclosed by a small portion of the upper end of the existing hammer spring.

The hammer bank includes a plurality of permanent magnets, and each of these permanent magnets is a common member shared by a plurality of magnet type hammer actuators. In the space between the hammer actuator,
It has been extended. The presence of the permanent magnet in the space between the magnet type hammer actuator and the magnet type hammer actuator serves to reduce the amount of leakage magnetic flux. When there is no permanent magnet in this space, the leakage magnetic flux is in communication between the rear portion of each magnetic pole piece pair and the rear portion of the adjacent magnetic pole piece pair.

Further in accordance with the present invention, the hammerbank comprises two separate elongate members having a single, integrally formed shaft sandwiched therebetween. The single shaft extends outward from both ends of the hammerbank, which facilitates reciprocally mounting the hammerbank, and the single shaft reduces the weight of the hammerbank. It has a hollow shape to reduce it. At the same time, the use of a single shaft improves the strength of the entire structure and eliminates the need to attach separate shafts to both ends of the hammerbank with an adhesive or the like. Furthermore, the hammerbank is mounted by inserting both ends of the shaft into the bearings on both sides. The single integral shape of the shaft is that of the shaft that is the mounting part. Make sure the shaft cores at both ends are coaxial.

In the hammer bank according to the present invention, the screw hole for mounting the hammer spring extends from the hammer spring mounting surface into the inside of the hammer bank, and the tip of the screw hole is
It communicates with the interior of each of the first plurality of openings forming part of the improved air cooling system. As a result,
Each screw hole is open at both ends, that is, one end is open to the outside of the hammer bank on the hammer spring mounting surface and the other end is the first plurality of openings formed in the hammer bank. One of the openings is open to the inside. Therefore, it is possible to fit a longer-sized hammer spring mounting screw, and it is also possible to project the tip of the screw into the inside of the cooling hole when more space is required. In addition, foreign substances such as oil are prevented from accumulating inside the screw holes.

In the hammerbank of the present invention, the upper portion of the cover assembly is secured to the hammerbank using a plurality of discrete magnetic clip assemblies attached to the hammerbank. This eliminates the need to magnetize the entire hammer bank, or nearly the entire hammer bank. Each magnetic clip assembly comprises a pair of pins, spaced apart from each other, mounted on an upper portion of the hammerbank and extending outwardly therefrom. An elongated base clip extends between the outer ends of the two pins, with both ends of the base clip secured to the outer ends of the pins. A permanent magnet is fixed to an intermediate portion between both ends of the base clip.
The magnetic attraction of the permanent magnet holds the portion of the cover assembly proximate to the permanent magnet in contact with the permanent magnet. By grinding the entire magnetic clip assembly including these base clips, permanent magnets, and the outer ends of the pins, a common reference exists in a desired relative position with respect to the hammerbank. A surface can be formed and the cover assembly is held against this reference surface.

[Embodiment] A preferred embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the shuttle assembly 10 together with other components of the printer 12, including a base support member 14, on which a cam drive mechanism 16 is mounted. Shuttle assembly 10
Includes an improved hammerbank 18 in accordance with the present invention, which is described in detail below. An elongated hollow air chamber 20 is mounted on the bottom surface of the base support member 14 on the side opposite the shuttle assembly 10, and the air chamber 20 is connected via a duct 22 to a blower 24 or other type of pressurized air source. Connected to.

The shuttle assembly 10 is formed as a replaceable integral modular unit inside the printer 12. By doing so, when manufacturing the shuttle assembly 10 in the factory, it is possible to make precise and delicate adjustments to the shuttle assembly 10 and the hammer bank 18 therein. After manufacturing, if the hammerbank 18 needs to be installed or removed during in-service use of the printer or in remote locations, the finely tuned, interchangeable shuttle assembly 10 is easy to use. It can be attached to and detached from the printer 12.

As shown in FIG. 1, the shuttle assembly 10 includes an elongated shuttle base 26, which is
A hammer bank 18 is placed on the top. The shuttle base 26 includes a lug 28 formed at an end portion 30 on the left hand side, and a through hole 32 is formed in the lug 28. The opposite right-hand end 34 of shuttle base 26 includes a pair of lugs (not shown in FIG. 1), each of which has a through hole formed therein.

The shuttle assembly 10 is removably mounted on the base support member 14 using bolts 36, 38 and 40. The bolt 36 extends through the hole 32 of the lug 28 to the inside of the base support member 14, thereby fixing the left-hand side end portion 30 of the shuttle base 36 to the base support member 14. Similarly, bolts 38 and 40 extend through the holes in the pair of lugs on the right-hand end 34 of the shuttle base 26 and extend into the base support member 14 to secure the right-hand end 34 of the shuttle base 26. It is fixed to the base support member 14. A pin 42 is erected upwardly at a position on the upper surface 44 of the base support member 14 extending substantially horizontally in the vicinity of the right-hand side end 34 of the shuttle base 26.
The pin 42 is inserted into a pin fitting hole formed on the bottom surface of the shuttle base 26 to position the shuttle base 26 at a correct position on the base support member 14. The pin fitting hole will be described later with reference to FIG.

Shuttle assembly 10 is easily and accurately mounted on base support member 14 inside printer 12 by the following method. The mounting method is such that the shuttle assembly 10 is mounted on the base support member 14 inside the printer 12 from above.
It goes down and the pin 42 is fitted in the pin fitting hole in the bottom surface of the right-hand side end 34 of the shuttle base 26. The shuttle assembly 10 is then rotated about the pin 42 to move the left hand side end 30 of the shuttle base 26 forward, the left hand side end 3
The platen holding plate on the 0 is moved until it fits in the plate receiving opening of the sheet feeding member 50. The paper feed member 50 is shown in FIG. A pair of paper feed members 5
0 and 52 cooperate to form the paper feed drive mechanism 54 of the printer 12, and the paper feed member 50 is the paper feed member on the left hand side of them. Once the platen retaining plate 46 is seated within the retaining plate receiving opening 48, bolts 36, 38 and 40 are threaded through the lugs into the base support member 14 and loosely tightened. Bolts 36, 38 and 40 are tightened after slight adjustments have been made to match the relative orientation of shuttle assembly 10 to cam drive 16. After this, Porto 5
8 and 60, the ribbon deck 56 as shown in FIG.
Is mounted on the front portion of the shuttle assembly 10. To remove the interchangeable shuttle assembly 10 from the printer 12, the procedure described above may be reversed.
Remove ribbon deck 56 from shuttle assembly 10 and then remove bolts 36, 38 and 40. As a result, the shuttle assembly 10 can be rotated around the pin 42, and the platen holding plate 46 can be pulled out from the holding plate housing opening 48 of the paper feeding member 50. In this state, the shuttle assembly 10 can be lifted, separated from the base support member 14, and removed from the printer.

The shuttle assembly 10 has a print area (print station) defined by a narrow gap of uniform gap width between the hammerbank 18 and the platen 106 adjacent thereto. A print paper of a predetermined width is arranged in this print area together with an ink ribbon of a predetermined length from the ribbon deck 56, and the hammer bank 18 prints on the print paper by a dot matrix method as described later. The print paper is moved within the print area of the shuttle assembly 10 by a normal method by the paper feed drive mechanism 54.
Dot lines are sent intermittently. The paper feed drive mechanism 54 uses the paper feed members 50 and 54 on both sides that engage with the feed holes formed on both sides of the print paper to feed the print paper upward.

The cam drive mechanism 16 may be, for example, of the type described in the aforementioned US Pat. No. 3,941,051 of Barrus et al.
The drive mechanism has a suitable conventional structure. Cam type drive mechanism 16
Includes a driven flywheel 64 connected to a cam 66. The cam 66 has a cam follower assembly 6 on one side thereof.
8 and the cam follower assembly 68 is connected to one end of the hammer bank 18. A cam follower assembly 68 with the balancing assembly 70 being a cam 66.
The engaging assembly 70 is engaged with the side surface on the opposite side to and is driven in an antiphase manner in a phase opposite to that of the hammer bank 18 in response to the rotation of the cam 66. The balancing assembly 70 compensates for the effects of reciprocal movement of the hammerbank 18,
Prevents shaking and other vibrations.

The hammer bank 18, in particular, the magnetic coil of the magnet type hammer actuator included in this hammer bank,
It is cooled by a device using pressurized air. The compressed air is supplied from the blower 24 shown in FIG. The blower 24 pressurizes the pressurized air into the elongated air chamber 20 through the duct 22, and the air chamber 2
Reference numeral 0 is connected to the bottom of the base support member 14 and is hermetically attached to the base support member 14 by a foam material sealing member 72 disposed on the upper surface of the air chamber 20. An elongated slot 74 is formed on the upper surface of the air chamber 20 to allow the air in the air chamber 20 to pass therethrough. The pressurized air passing upward through the slots 74 flows into and passes through the four openings 76 formed in a row in the base support member 14. These openings 76 are formed in an elongated shape,
Above the slot 74 formed in the air chamber 20,
It is formed at a position substantially overlapping with the slot 74.

As described below, the shuttle base 26 of the shuttle assembly 10 has four openings formed in the bottom thereof when the shuttle assembly 10 is mounted on the base support member 14. In addition, it is arranged at a position overlapping the opening 76 of the base support member 14. From the air chamber 20, pressurized air passing upward through openings 76 in the base support member 14 flows into the shuttle assembly 10 through those openings formed in the bottom of the shuttle base 26.

FIG. 3 is an exploded perspective view showing the hammer bank 1.
8, cover assembly 78, elongated platen assembly 80, and cam follower assembly 6 included in shuttle assembly 10 as part of its components.
8 is illustrated. The hammerbank 18 includes a hollow shaft 82 formed as a single, unitary member that is mounted within the hammerbank 18 and extends the length of the hammerbank 18. Both ends of the hollow cylindrical shaft 82 extend outward from both ends of the hammer bank 18, and a pair of extending shaft portions 84 and 86 having a predetermined length are exposed to the outside of the hammer bank 18. As will be described below, these extended shaft portions 84 and 86 are fitted inside the linear movement sleeve bearing mounted on the shuttle base 26, whereby the hammer bank 18 is moved in the longitudinal direction of the shaft 82. It can be reciprocated freely.
The cam follower assembly 68 is attached to the distal end portion of the extension shaft portion 84, and is engaged with the cam 66 of the cam type drive mechanism 16 to reciprocate the hammer bank 18. FIG. 4, which is a partial cross-sectional view, shows a single shaft 82 extending inside the hammer bank 18 over the entire length of the hammer bank 18.

The cover assembly 78 is mounted on the hammerbank 18 and contains a predetermined length of ink ribbon 88 from the ribbon deck 56. The cover assembly 78 has a shape folded into two and includes a front portion 90 and a rear portion 92 thereof.
An ink ribbon 88 having a predetermined length is arranged between the two, and a lower edge portion 94 thereof is fixed to the hammer bank 18 along the longitudinal direction of the hammer bank 18. The cover assembly 78 is fixed to the hammer bank 18 along the lower edge portion 94 thereof via the fasteners 96 and the like.
Is connected to both ends of the lower edge 94, and the bolt 9
It is fixed to both ends of the hammer bank 18 by 8 and 100.

An upper edge 102 of the cover assembly 78 opposite the lower edge 94 is provided with a plurality of magnetic clip assemblies 10.
4, which are held in a fixed position relative to the upper portion of the hammerbank 18, these magnetic clip assemblies 104 being spaced apart from one another along the upper portion of the hammerbank 18. It is placed in the state. Magnet type clip assembly 1
04 will be described in detail later with reference to FIG. 19, but after the magnet-type clip assembly 104 is mounted on the hammerbank, the magnet-type clip assembly 104 is subjected to precision grinding to obtain the hammerbank 18 It is possible to define a reference plane which lies in a precise relative position to the upper part of the. The upper edge 102 of the cover assembly 78 is held in contact with this reference surface of the magnet type clip assembly 104 by a magnetic attraction force.

As already mentioned, the cover assembly 78 mounted on the hammerbank 18 forms a narrow gap of uniform width dimension, which is the print area in which the print paper is placed (print station). Is defined. The print station is formed by a cover assembly 78 and an elongated platen 106,
06 constitutes the platen assembly 80 together with the pair of shafts 108 and 110 at both ends thereof. The platen assembly 80 is mounted substantially parallel to the hammer bank 18 and apart from the hammer bank 18, and the shafts 108 and 110 are coaxial with each other and the longitudinal axis of the shaft 82 of the hammer bank 18. It is located on a parallel axis. The platen 106 supports a print paper 112 having a predetermined width and having openings 114 on both side edges. Openings 114 on both side edges of the print paper 112
2 are engaged by paper feed members 50 and 52 shown in FIG. 2, which intermittently move the print paper 112 upward through the print station.

In the present embodiment, the hammer bank 18 is provided with a total of 66 hammer springs 116, and these hammer springs 116 are mounted on the hammer bank 18 in a state in which they are spaced apart from each other in the longitudinal direction. Only four of these hammer springs are shown in FIG. 3 for the sake of clarity. The hammer spring 116 is mounted on the hammer spring mounting surface 118 along the mounting surface 118, and the hammer spring mounting surface 118 extends on the hammer bank 18 in the longitudinal direction thereof. . The lower end of each hammer spring 116 is fixed to the mounting surface 118 with a screw 120, and the screw 120 is attached to the mounting plate 122 and the hammer spring 11.
6 is screwed into the screw hole 124 through the lower end portion of the hammer 6, and the screw hole 124 extends from the mounting surface 118 to the hammer bank 1.
8 is formed so as to extend inside.

Each hammer spring 116 has a pair of pole pieces 1 individually.
26 and 128 are combined, and the pair of magnetic pole pieces are mounted inside the groove 130. The groove 130 is formed in the upper portion of the hammer bank 18, and extends substantially parallel to the hammer spring mounting surface 118 and apart from the mounting surface 118. The pole pieces 126, 128 form part of a magnet type hammer actuator for actuating the hammer spring 116. Pole piece 12
6, 128 comprises a permanent magnet 132, which is between their pole pieces 126 and 128 and in the groove 13
It is arranged inside 0. The coil assembly 134 also forms part of the magnet type hammer actuator, which coil assembly 134 includes a first pole piece 126.
The first magnetic coil 136 and the second magnetic pole piece 1 mounted on the
And a second magnetic coil 138 mounted on. The first magnetic coil 136 and the second magnetic coil 138 are arranged outside the groove 130 and near the upper end which is the free end of the hammer spring 116.
Located above 26 and 128.

The hammer spring 116 is made of a magnetic elastic material such as spring steel. Each hammer spring 116 is normally held in the retracted position, and when in the retracted position, the spring force is slightly applied to the hammer spring 116. Further, when in the retracted position, the permanent magnet 1
The permanent magnets 132 are attracted to the tips of the magnetic pole pieces 126 and 128 by the action of 32.
And 128 and hammer springs 11 close to them
The magnetic circuit formed by passing through the upper end of 6 is completed. Each of the hammer springs 116 has a dot printing impact tip 140 attached to an upper end portion which is a free end thereof. Each of the impact tips 140 is disposed in the vicinity of a pair of openings 142 formed in the front portion 90 and the rear portion 92 of the cover assembly 78 and provided individually for each impact tip.

During printing, that is, when the hammer bank 18 is reciprocating relative to the platen 106, the individual hammer springs 116 are selectively released or "fired" and thereby supported by the platen 106. Print paper 112
Dots are printed on top. The opening of each hammer spring 116 is performed by exciting the first coil 136 and the second coil 138 of the coil assembly 134 combined with the individual hammer springs, and the exciting time at that time is the time of the permanent magnet 132. The time is sufficiently long to allow the upper end, which is the free end of the hammer spring 116, to be released from the pole piece and to be blown out by overcoming the attraction and holding force by the magnetic force. The hammer spring 116 has the pole piece 12
When moved away from 6, 128, the impact tips 140 project through a pair of openings 142 in the cover assembly 78 provided for the individual impact tips, and the front and rear portions 90 and 92 of the cover assembly 78 are removed. The ink ribbon 88 disposed between the two is hit (impacted) against the print paper 112 supported by the platen 106. After the impact, the hammer spring 116 bounces back to the retracted position and comes into contact with the magnetic pole pieces 126 and 128. The hammer spring 116 remains in this retracted position in preparation for the next opening. The return movement of the hammer spring 116 to the retracted position is damped by the Kapton strip 143. The Kapton strip 143 is provided between the hammer spring mounting surface 118 and the groove 130 containing the magnetic pole pieces 126 and 128.
It extends in the longitudinal direction of the hammer bank 18. The Kapton strip 143 is disposed in the vicinity of the intermediate portion of the hammer spring 116, and is formed into a strip shape by stacking several layers of Kapton.

As described above, the cam follower assembly 68 is mounted on the extension shaft portion 84 in order to cause the hammer bank 18 to reciprocate in response to the cam type drive mechanism 16. The cam follower assembly 68 includes a roller bearing 144 rotatably mounted on the yoke 146. The roller bearing 144 projects outward from the yoke 146 and engages with the cam 66 of the cam type drive mechanism 16. The yoke 146 is connected to the bearing assembly 148 via a collar 150 formed on the back surface of the yoke 146. The collar 150 passes through the washer 152, the coil-shaped shuffle spring 154, and the washer 156,
Reaching the end of the bearing assembly 148, the bearing assembly 148 is fitted with a reservoir 158, which is the bearing assembly 1.
It is engaged with an oil-impregnated felt member provided at the end of 48.

The bearing assembly 148 is attached to the tapered end 162 of the extension shaft portion 84. An adjustment screw (not shown) is loosely fitted inside the collar 150, and the adjustment screw is mounted inside the tapered end portion 162 of the extension shaft portion 84. This adjusting screw regulates the range in which the yoke 146 can move in the direction away from the tapered end 167, and at the same time, the yoke 146 resists the elastic resistance of the spring 154 and is closer to the tapered end 162. By allowing a limited amount of movement, the roller bearing 144 cushions the impact of the cam 66 following the cam 66.

The hammer bank 18 to which the cover assembly 78 and the cam follower assembly 68 are attached, and the platen assembly 80 are mounted on the shuttle base 26,
The shuttle base 26 is shown in detail in FIG. The shuttle base 26 has an elongated shape, and a space between the left-hand side end portion 30 and the right-hand side end portion 34 thereof has a substantially rectangular shape. As previously described with respect to FIGS. 1 and 2, the left hand end 30 includes a lug 28 having a through hole 32 for the bolt 36 to pass through. The right-hand side end portion 34 of the shuttle base 36 has a pair of lugs 1 which are separated from each other.
64 and 166, these lugs having through holes 168 and 1 for inserting the bolts 40 and 42 shown in FIG.
70 are formed.

The shuttle base 26 is formed in a shape that defines bearing blocks 178 and 180 at the right-hand side end portion 34 and the left-hand side end portion 30, respectively. A recess 182 is formed in the bearing block 178, and a recess 184 is formed in the bearing block 180. These recesses 182 and 184 are formed so as to be suitable for mounting a linear movement sleeve bearing that supports the extended shaft portions 84 and 86 of the hammerbank 18.
This allows the hammerbank 18 to reciprocate along the longitudinal axis of the shaft 82, and the longitudinal axis of the shaft 82 extends in the longitudinal direction of the shuttle base 26.

The shuttle base 26 is further formed in a shape that defines a bearing surface 186 behind the recess 182 and adjacent to the recess 182, and a bearing surface 188 behind the recess 184 and adjacent to the recess 184. These bearing surfaces 186 and 18
8 is configured to support the shafts 108 and 110 at both ends of the platen 106, respectively. These shafts 108 and 110 are properly retained on the bearing surfaces 186 and 188 by the clamping assemblies 190 and 192 shown in FIGS. 8-11. The clamping assemblies 190 and 192 allow rotation of the shafts 108 and 110 that they hold, to allow the angle of the platen 106 to be varied. The shuttle base 26 includes bearing surfaces 186 and 18
8, openings 194 and 196 are provided in the vicinity of which the adjustment mechanism for adjusting the lateral positions of the shafts 108 and 110 is fitted.

Shuttle base 26 further includes a detent block 198, which is a detent assembly 200.
Form part of. The detent assembly 200, which is shown in detail in the cross-sectional view of FIG. 13, is a mechanism that prevents rotation of the hammerbank 18 while allowing its reciprocation.

As shown in FIG. 5, shuttle base 26 includes a bottom portion 202 extending longitudinally of shuttle base 26 between front and rear wall portions 204 and 206 facing each other. Bottom 202, front wall 204, and rear wall 20
6 extends along the longitudinal direction of shuttle base 26 between opposed bearing blocks 178 and 180. The detent block 198 projects outward from the front wall portion 204 at the longitudinal middle portion of the front wall portion 204. The bottom portion 202 is formed to define three cross members 208 extending between the front wall portion 204 and the rear wall portion 206. These cross members 2
08 cooperates with transversely mounted bearing blocks 178 and 180 to divide the length of the bottom 292 into four separate compartments 210, 212, 214 and 216.

These four compartments 210 inside the shuttle base 26,
Each of 212, 214, and 216 is formed with an opening 218 that penetrates the small chamber. This is also illustrated in Figure 12, which is a bottom view of assembled shuttle assembly 10. The four separate openings 218 are formed in isolation from each other, each in the shape of a slot,
Further, they are positioned so as to overlap the openings 76 of the base support member 14, and the pressurized air flowing into the openings 76 flows into the openings 218. Bottom 20 of shuttle base 26
The compressed air that has flowed into the opening 218 of the second chamber 218 is
Flowing over 12, 214 and 216 into an elongated cavity extending longitudinally of shuttle base 26. As will be explained below, this elongated cavity is used when the hammer bank 18 is mounted on the shuttle base 26.
A common high pressure chamber is formed at the rear of the bottom of the hammer bank 18.

FIG. 6 shows the shuttle base 26, the base support member 14,
It is a side view of the air chamber 20 and the duct 22, and is a side view which made most sections. As described above with reference to FIG. 1, the blower 24 causes the pressurized air to flow through the duct 22 into the hollow interior of the air chamber 20. The compressed air inside the air chamber 20 is
0 through the slots 74 on the top surface and into the four individual openings 76 formed in the base support member 14.
As shown in FIG. 6, the pressurized air flowing into the opening 76 passes through the opening 76 and flows into the opening 218 formed in the bottom portion 202 of the shuttle base 26. Pressured air is opening 21
8 to the small chambers 210, 212, 21 of the shuttle base 26
4 and 216 and from there into a common high pressure chamber at the bottom of the hammerbank 18, as described below. The joint surface between the horizontal upper surface 44 of the base support member 14 and the bottom portion 202 of the shuttle base 26 is sealed with a sealing tape (sealing tape) 220, which is shown in FIGS. 1 and 6. Has been done.

7 to 13 show the shuttle base 2 which has been assembled.
It is the figure which looked at 6 from various directions. The extended shaft portion 84 at one end of the hammer bank 18 is provided in the bearing block 17
8 is slidably supported inside a linear movement sleeve bearing 222 placed inside a recess 182 formed in the No. 8. Recess the linear bearing sleeve 222 for the recess 1
A bearing cap 224 held inside 82 is arranged so as to cover the linear movement sleeve bearing 222. Similarly, the extended shaft portion 86 at the other end of the hammer bank 18 is slidably supported inside the linear movement sleeve bearing 226 described inside the recess 184 formed in the bearing block 180. . The bearing cap 228 fixed to the bearing block 180 is used for the linear movement sleeve bearing 22.
6 is held inside the recess 184.

As previously described with respect to FIG. 3, each hammer spring 116 has a coil assembly 1 associated with it.
It is selectively opened by exciting 34. The lead wire 23 of one of those coil assemblies 134
0 is shown in FIG. Separate coil assemblies 134 for 66 individual hammer springs 116
Are connected to a control circuit provided outside the shuttle assembly 10. This connection is made up of a number of leads 23
The lead wires such as 0 are combined into six lead wire buses 232 arranged in the longitudinal direction of the hammer bank 18. The lead wire bus 232 is best seen in FIGS. 6 and 8 and extends upwardly from the coil assembly 134 as well as the clamping bars 234 and 23.
6 are clamped in a state of being aligned on the side opposite to the hammer bank 18. Although lead bus 232 is shown broken away in FIGS. 7 and 8 directly below clamping bars 234 and 236, the ends of those lead buses 232 are provided with a connector and their The connector is fixedly connected to a mating connector provided on the printer 12. This completes the connection from the coil assembly 134 to the control circuitry, which is done after mounting the shuttle assembly 10 inside the printer 12.

FIG. 12 shows details of the detent assembly 13. The anti-rotation assembly 200 prevents the rotation of the hammer bank 18 about the longitudinal axis of the shaft 82 on both sides of the metal plate 238 attached to the rear side of the central portion of the hammer bank 18 and at the same time. By holding the hammer bank 18 so that the hammer bank 18 can reciprocate by allowing the relative sliding movement of the plate 238, the rotation of the hammer bank 18 is stopped. A substantially hemispherical pad 240 is slidably engaged with one side surface of the metal plate 238,
On the other hand, on the side surface on the opposite side of the metal plate 238, a slidable reaction receiving slide member 244 biased by a spring is provided.
A reaction receiving pad 242 fixed to one end of the is slidably engaged.

The platen assembly 80 includes a platen handle 246. The platen handle 246 is connected to the shaft 108 at one end of the platen 106 via a mechanism that includes an adjustable shaft collar 248.
Shaft collar 248 is used to adjust the relative angle of platen handle 246 with respect to platen 106.

FIG. 12 is a bottom view of shuttle assembly 10, showing bottom 202 of shuttle base 26. As shown in FIG. 12, the bottom portion 202 is formed with four openings 218 for allowing pressurized air to flow from the air chamber 20 through the base support member 14. The bottom portion 202 of the shuttle base 26 is further provided with a bush 250 between the lug 164 and the lug 166 of the right-hand side end portion 34 thereof in the vicinity of the lugs. This bush 250 is
An opening 2 having a size such that the pin 42 attached to the horizontal upper surface 44 of the base support member 14 is fitted tightly inside.
52.

Third showing the front part 253 of the hammerbank 18
As previously described with respect to the figures, this front portion 253 has a hammer spring mounting surface 118 for mounting the hammer spring 116 and a groove 130 for mounting a number of pole pieces 126, 128 and a permanent magnet 132. including.
FIG. 3 also illustrates the bottom surface 254 of the hammerbank 18.

FIG. 4 shows the bottom surface 254 of the hammerbank 18 with the portion of the hammerbank 18 opposite the front portion of the hammerbank 18 shown in FIG. As shown in FIG. 4, the hammerbank 18 has a back surface 256 that connects to the bottom surface 254 via an angled lower surface 258. The monolithic shaft 82 extends along the lower portion of the hammer bank 18 and directly above the bottom surface 254 and between the back surface 256 and the opposite front portion 253 of the hammer bank 18. Penetrates inside. Hammer bank 1
8 is the extension shaft portions 84 and 86 of the hammer bank 18.
Are placed inside the shuttle base 26 by arranging and inside the linear motion sleeve bearings 222 and 226.
Is mounted inside the recesses 182 and 184 of the bearing blocks 178 and 180 of the shuttle base 26 as described above. FIG. 13 shows that the hammer bank 18 is mounted inside the shuttle base 26 as described above.

As already explained with reference to FIG. 5, shuttle base 2
6 includes a bottom wall 202 extending between the front wall portion 204 and the rear wall portion 206 in the longitudinal direction of the shuttle base 26. These bottom wall 202, front wall 204, and rear wall 206 of shuttle base 26 are shown in FIG. 13, and also in FIG. 15, which is a cross-sectional view of shuttle assembly 10 with hammerbank 18 removed. It is shown. FIG. 15 shows the shuttle base 26 between the bearing blocks 178 and 180 on both sides connected to the front wall portion 204.
2 shows a shuttle shroud 260 extending in the longitudinal direction of the. The shuttle shroud 260, also shown in FIG. 13, is partially shaded by the detent assembly 200, which is located exactly in the center of the shuttle base 26.

The shuttle shroud 260 cooperates with the front wall 104 and the bottom wall 202 of the shuttle base 26 to form a continuous, hermetic, airtight enclosure that extends in the longitudinal direction of the hammerbank 18. The bottom surface 254 of the hammer bank 18 and the back surface 25
6 and extends to the upper portion 261 of the hammerbank 18. A polyester film 262 is hermetically sealed between the upper portion 261 of the hammer bank 18 and the shuttle shroud 260, and the polyester film 262 is adhered to the uppermost lip portion 264 of the shuttle shroud 260 by the double-sided tape 266. ing. Polyester film 262 and double-sided tape 2
66 is most clearly shown in FIG. 15 and is the bearing blocks 17 on both sides of the shuttle base 26.
Between 8 and 180 extends the entire length of shuttle shroud 260. When the hammer bank 18 reciprocates inside the shuttle base 26, the polyester film 262 having flexibility and elasticity serves to prevent the hammer bank 18 from moving.
Is leaning against the upper portion 261 of the above, and maintains a substantially airtight state between them.

As shown in FIG. 13, the hammer bank 1 is provided between the rear wall portion 206 of the shuttle base 26 and the hammer bank 18.
There are 8 narrow openings along the length. The opening 168 is made airtight by the foam material tape 270. The foam tape 270 is attached to the upper surface of the rear wall 206.
It is attached along the longitudinal direction of the rear wall portion 206, and extends in contact with a narrow portion of the bottom surface 254 of the hammer bank 18 close to the front portion 253 of the hammer bank 18. Hammer bank 18 is shuttle base 26
The foam tape 270 having flexibility and elasticity when reciprocating in the interior of the shuttle base 26 is
The space between 06 and the hammer bank 18 is kept airtight.

Accordingly, it can be seen that the hammerbank 18 is located within the elongated cavity 272 inside the shuttle base 26 of the shuttle assembly 10. This elongated cavity 2
The upper portion of 72 is covered with a shuttle shroud 260, and is further sealed with a polyester tape 262. A lower portion of the elongated cavity 272 opposite to the elongated cavity 270 is sealed with a foam material tape 270. Both ends of the elongated cavity 272 located inside the bearing blocks 178 and 180 on both ends of the shuttle base 26, which are located inside the bearing blocks 178 and 180, are hermetically sealed by a pair of hermetically sealed structures on both sides. One of the sealed structures is shown in FIG. As shown in FIG. 15, the lower end seal 274 is attached to the inside of the shuttle base 26 by a pair of screws 276 and a washer 278. The screw 276 penetrates the bottom portion 202 of the shuttle base 26 and is screwed into the inside of the lower end seal 274 to fix the lower end seal 274 at that position. The lower end seal 274 extends across the bottom 202 between the front wall portion 204 and the rear wall portion 206, and its upper surface 280 has a top surface 280 of the hammer bank 18 at one end thereof. It is formed to fit the lower part. The bottom seal 274 cooperates with the end of the hammerbank 18 to create a generally airtight seal at one end of the elongated cavity 272. Another lower end seal, similar in shape to this lower end seal 274, is attached to the other end of the interior of shuttle base 26 and mates with the other end of hammerbank 18 to accommodate the other end of the elongated cavity. It creates a sealed state at the end.

As described above, the blower 24 causes the pressurized air to flow into the inside of the air chamber 20 through the duct 22, and the compressed air is discharged from the air chamber 20 to the base support member 14.
Opening 76 of the shuttle base 26 and opening 2 of the bottom 202 of the shuttle base 26
And flows through. The pressurized air enters the elongated cavity 272 as it passes through the opening 218 in the bottom 202 of the shuttle base 26. A plurality of openings are formed in the hammer bank 18, and these openings allow pressurized air,
It leads from the elongated cavity 272 via the inside of the hammer bank 18 to the area outside the hammer bank 18 and below the coil assembly 134. Air enters this region below the coil assembly 134 with increased velocity and significant turbulence. As a result, turbulent high-speed air flows around the coil assembly 134, so that the cooling action is enhanced and the coil assembly 134 is cooled.
It is possible to obtain a considerable amount of cooling effect inside the narrow space near the.

The plurality of openings formed inside the hammer bank 18 include a first plurality of openings 282 and a second plurality of openings 284. The first plurality of openings 282 is shown in FIG. 3 and therein. The first plurality of openings 282 are provided at substantially equal intervals along the longitudinal direction of the hammer bank 18, and each of the bottom surfaces 254 of the hammer bank 18 is provided.
And a substantially horizontal surface 286 located at the bottom of the first high-pressure chamber 288, extending substantially vertically. The second plurality of openings 284, as shown in FIG.
From the back surface 256 to the inside of the hammer bank 18 extending substantially horizontally. Like the first plurality of openings 282, the second plurality of openings 284 are also provided along the longitudinal direction of the hammer bank 18 at substantially equal intervals. As shown in FIG. 13, each of the second plurality of openings 284 passes from the back surface 256 through the back wall portion 290 of the hammerbank 18 to the second high pressure chamber 29.
The second high pressure chamber 292 is formed by an internal cavity extending in the longitudinal direction of the hammer bank 18. These openings 284 pass through the second high pressure chamber 292 in the horizontal direction from the rear wall portion 290, further pass through the wall portion 294, and continue to the substantially vertical surface 296 of the first high pressure chamber 288.

FIG. 14 illustrates a small portion of the first high pressure chamber 288, which portion includes a horizontal surface 286 and a vertical surface 296,
The surfaces intersect at the bottom of the first high pressure chamber 288. FIG. 14 illustrates four of the first plurality of openings 282 that are arranged substantially vertically and have their ends open to the horizontal surface 286. FIG. 14 further illustrates four of the second plurality of openings 284 that extend horizontally and have their ends open to the S vertical surface 296. As shown in FIG. 14, the first plurality of openings 282 and the second
The plurality of openings 284 are alternately arranged along the longitudinal direction of the first high-pressure chamber 288, and thus are arranged zigzag with each other along the longitudinal direction of the hammerbank 18.

As shown in FIG. 13, the elongated cavity 272 between the hammer bank 18 and the shuttle base 26 forms a high-pressure air chamber common to the first plurality of openings 282 and the second plurality of openings 284. In this embodiment, the elongated cavity 2
Air is introduced into this common high pressure chamber formed by 72 at a pressure of about 1.8 inches of water column (about 45.7 mm aq.). This allows a flow rate of about 30 cubic feet per minute of air to enter the common high pressure chamber and from there through openings 282 and 284 into hammerbank 18. As shown by the arrow in FIG. 13, the pressure air that has flowed into the common high-pressure chamber formed by the cavity 272 splits there, part of which is in the first plurality of openings 282 and the rest is the second plurality of openings 28.
Inflow to 4, respectively. The air that has flowed into the first plurality of openings 282 flows upward in the openings and then flows out of the openings 282 in the horizontal plane 286 as shown in FIG. Second
The air that has flowed into the plurality of openings 284 passes through the rear wall portion 290 and flows into the second high pressure chamber 292. The air flows from the second high pressure chamber 292 to a portion subsequent to the second plurality of openings 284 formed in the wall portion 294. This air is the first
As shown in FIG. 4, at the vertical surface 296, it flows out from the second plurality of openings 284.

Since the first plurality of openings 282 and the second plurality of openings 284 are formed in the above-described manner, when the compressed air flows from the common high pressure chamber formed by the cavity 272 to the first high pressure chamber 288. To increase its speed. Furthermore, the fact that it is formed in this manner and the fact that the two sets of openings 282 and 284 are arranged in a zigzag manner combine with the air flowing into the first high-pressure chamber 288 to a considerable degree of turbulence. Is producing. As shown in FIG.
The air that horizontally flows into the first high pressure chamber 288 from the second plurality of openings 284 after being rotated in the second high pressure chamber 292 is
The vertical jets from the first plurality of openings 282 that are staggered are mixed in an extremely turbulent state. As a result, it has been found that the first high-pressure chamber 288 is filled with the air that is flowing at a high speed and in a very turbulent state, which greatly enhances the cooling effect on the air.

Turbulent high-speed air in the first high-pressure chamber 288 flows upward and reaches the periphery of the coil assemblies 134, where the air is in the first magnetic coil 136 and the second magnetic coil 138 of each coil assembly 134. Flow around and on the surface of. Even though the coil assemblies 134 are arranged relatively close together, and in addition generate a considerable amount of heat by the coil assemblies, the high speed turbulence inside the first high pressure chamber 288 is high. It has been found that air exerts more than sufficient cooling effect without the need to use a bulky mechanism such as a radiation fin structure.

A first high pressure chamber 288 having a horizontal surface 286 at the bottom is defined on one side by a vertical surface 296. First high pressure chamber 28
8 has a side surface opposite to the vertical surface 296 partially
The free upper end of the hammer spring 116 in the region near the coil assembly 134 is typically the free upper end of the hammer spring 116.
It is in the retracted position attracted by 6, 128 and located in the region near the coil assembly 134. Exists in a position. The adjacent hammer springs 116 and the hammer springs 116 are separated from each other by a relatively narrow space. In order to prevent turbulent high speed air inside the first high pressure chamber 288 from escaping from the space between the hammer springs 116 without passing through the surface of the coil assembly 134, the air dam is It is equipped. This air dam includes a first magnetic coil 136 and a second magnetic coil 1 of each coil assembly 134.
Formed of a large flange on a bobbin that holds 38 and 38. This is best shown in FIGS. 20 and 21, which illustrate one of the coil assemblies 134.

As shown in FIGS. 20 and 21, the coil assembly 134 includes a first magnetic coil 136 and a second magnetic coil 138 mounted on the bobbin assembly 298. The bobbin assembly 298 includes a base 300, the base 3
00 is placed on the hammer bank 18 at a position just outside the groove 130. The bobbin assembly 298 includes a first bobbin 302 and a second bobbin 304 that project outwardly from the base 300 and carry a first magnetic coil 136 and a second magnetic coil 138, respectively. ing. These bobbins 302 and 304 have hollow interiors which are shaped so that the front portions of the pole pieces 126 and 128 are inserted. The first bobbin 302 includes the first pole piece 1
At its outer end located near the tip of 26, the flange 3
06 is formed. Similarly, the second bobbin 304
Has a flange 308 formed on the outer end of the second magnetic pole piece 128 located near the tip thereof.

These bobbin flanges 306 and 308, as indicated by the narrow interface between them,
Formed very closely. Furthermore, pair 1 of pole pieces
Due to the fact that 26, 128 are arranged relatively close to each other along the longitudinal direction of the groove 130, the plurality of bobbin assemblies 298 are arranged relatively close to each other, and therefore the flange of one bobbin assembly 298 is arranged. 306, 3
08 extends in close alignment with the flanges 306 and 308 of the bobbin assemblies 298 on both sides thereof. Therefore, in each bobbin assembly 298, its bobbin flanges 306 and 308 are connected to each other,
In addition to forming almost continuous walls at the outer ends of the magnetic coils 136 and 138, a plurality of magnetic pole pieces 126
Each flange 306 at the outer end of the
At the outer end of the groove 130, a substantially continuous wall is formed along the longitudinal direction of the groove 130. Similarly, the respective flanges 138 at the outer ends of the magnetic pole pieces 128 form almost continuous walls along the longitudinal direction of the groove 130 at the outer ends of the magnetic coil 138. The wall or air dam formed in this manner prevents turbulent high-speed air in the first high-pressure chamber 288 from flowing out in large quantities through the gap between the hammer springs 116 adjacent to each other. To effectively prevent. The air dam allows virtually all air to pass around the magnetic coils 136 and 138 of each coil assembly 134. After this, the air flows straight up and out of the shuttle assembly 10, as indicated by the top arrow in FIG.

As shown in FIG. 13, the hammerbank 18 is comprised of two separate elongated members 312 and 314, which extend with the shaft 82 throughout the length of the hammerbank 18. The first elongate member 312 forms the front portion 253 of the hammerbank 18. The lower portion of the elongated member 312 is the hammer spring mounting surface 1
18 and the first high pressure chamber 288 are formed. The pole piece 1 is provided on the upper portion of the elongated member 312 opposite to the lower portion.
Groove 13 for receiving 26 and 128 and permanent magnet 132
0 is formed, and the upper end portion of this upper portion forms the top portion 261 of the hammer bank 18. Slender portion 312
A portion of the bottom of the shaft opposite to the hammer spring mounting surface 118 is formed to receive the outer peripheral surface of the shaft 82 over its entire length. The second elongate member 324 has a first elongate member 312 at its lower and upper portions.
Is connected with. The lower portion of the second elongated member 314 is the majority of the bottom portion 254 of the hammerbank 18 and the back surface 256.
And all of the angled bottom surface 258. The lower portion of the second elongate member 314 is shaped to receive the outer peripheral portion of the shaft 82 over its entire length. A portion of the second elongate member 314 is part of the first elongate member 31.
2 away from the first elongated member 312.
A second high pressure chamber 292 is formed on the outer peripheral portion of the shaft 82 in cooperation with the above.

As described above, each hammer spring 116 is attracted to the magnet type hammer actuator associated therewith and held in the retracted position, and is released, that is, fired from the hammer actuator. The magnet type hammer actuator includes two magnetic pole pieces 126 and 128, a permanent magnet 132, and a coil assembly 134, and the coil assembly 134 includes a first magnetic coil 136 and a second magnetic coil 138. Since the hammer bank 18 has a compact shape, the magnet type hammer actuator and the magnet type hammer actuator which are adjacent to each other are arranged very close to each other. The operation is made extremely small by some features of the hammer bank 18. One of those features is that, with the exception of the permanent magnet 132, there is a magnetic member extending beyond it over two or more magnet type hammer actuators, namely, two.
There is no magnetic member common to one or more magnet type hammer actuators. The elongated member 312 of the hammerbank 18 including the groove 130 is made of a non-magnetic material,
In this embodiment, it is made of aluminum. The second elongate member 314 of the hammerbank 18 is also made of aluminum, and so is the shaft 82. The only magnetic member extending between adjacent magnet type hammer actuators is the permanent magnet 132.
Allows no or very little leakage flux to communicate between adjacent hammer actuators.

In this embodiment, one separate permanent magnet 132 is associated with each of the four groups of magnet type hammer actuators. The individual permanent magnets 132 are mounted end to end in contact with each other, thereby forming a substantially continuous permanent magnet structure over the entire length of the groove 130. FIG. 16 illustrates one of the permanent magnets 132 with the four magnet hammer actuator pole pieces associated therewith. The permanent magnet 132 has an elongated and substantially rectangular shape, and is disposed between the rear portion 316 of the magnetic pole piece 126 and the rear portion 318 of the magnetic pole piece 128 in each magnetic pole piece pair. Rear portion 316 of pole pieces 126 and 128
And 318, as well as the permanent magnet 132 disposed therebetween, are mounted within the groove 130 using a suitable non-magnetic adhesive such as epoxy. As already mentioned,
Each pole piece pair 126, 128 has its front portion 320, 3
22 extends outward from the groove 130, and magnetic coils 126 and 128 of a coil assembly 134 individually provided for each pair of magnetic pole pieces are mounted on the front portion of the groove 22.

FIG. 17 is a front view of the permanent magnet 132 and the four pairs of pole pieces 126, 128 associated therewith. Permanent magnet 1
It is very advantageous that 32 extends between adjacent pole piece pairs 126, 128. It has been found that if there is no permanent magnet 132 between adjacent pairs of pole pieces, there will be significant leakage flux between the top pole piece 126 and the bottom pole piece 128. On the other hand, a pair of magnetic pole pieces 126 adjacent to the permanent magnet 132,
By extending through the space between the magnetic poles 128, that is, existing inside the space, the leakage flux between the upper magnetic pole pieces 126 and the lower magnetic pole pieces 128 becomes extremely small. It is known that As shown in FIG. 17, magnetic force lines representing the leakage magnetic flux extend from the first magnetic pole piece 126 and the second magnetic pole piece 128 to the permanent magnet 132, and these magnetic force lines terminate there.

Since only the non-magnetic material is used between the magnet type hammer actuators except for the permanent magnets 132, further, between the magnetic pole moving piece pairs of the adjacent individual magnet type hammer actuators, Since the permanent magnets are extended, it has been found that the unwanted interaction between the adjacent magnet type hammer actuators is extremely small. In this example, it has been found that this interaction is only about 1 / 10,000 or less.

FIG. 18 is a sectional view of a part of the hammer bank 18,
Set the hammer spring mounting surface 118 to the hammer spring 1
It is a figure shown with 16, a screw 120, and a mounting plate 122. As described above with reference to FIG. 3, the lower end of each hammer spring 116 is attached to the mounting surface 1 by an individual screw 120.
The screw 120 is fastened to the bearing 18, and the screw 120 penetrates the mounting plate 122 and the lower end of the hammer spring 116 and is screwed into the hammer bank 18. A separate mounting plate 122 is used for fixing each pair of hammer springs 116.

Screw 120 for mounting the hammer spring 116
Is screwed into a screw hole 324 formed in the hammer bank 18 as shown in FIG. Screw hole 324
Has one end opening on the hammer spring mounting surface 118,
The first plurality of openings 28 formed at the hammer bank 18 at the other end
It is open to one of the two and is therefore a bottomless hole. The hammer bank 18 has a hammer spring mounting surface 1
On the 18, there are 66 screw holes 324 formed at intervals along the longitudinal direction of the hammer bank 18, by which 66 hammer springs 116 are mounted. Since a sufficient number of the first plurality of openings 282 are formed at intervals along the longitudinal direction of the hammer bank 18,
Each of the screw holes 324 is open to one of the first plurality of openings 382.

These threaded holes 324 formed in hammerbank 18 provide several advantages. For one, screw holes 324
From the hammer spring mounting surface 118 to the first plurality of openings 2
This screw hole 324 is relatively long because it extends all the way to one of the openings 82.
As a result, the hammer spring mounting screw 122 can be made relatively long, and the hammer spring 11
6 can be attached more firmly. Furthermore, the screw 120 can completely penetrate the screw hole 324, and if necessary, the first plurality of openings 2 that follow the screw hole 324.
It is also possible to extend to the inside of 82. Screw hole 3
The bottomless shape of 24 also brings the advantage of eliminating foreign matter such as dust. For example, when a hammer spring mounting screw is screwed into a screw hole with a bottom, oil residues and other foreign matter are trapped between the tip of the screw and the bottom of the screw hole and remain there. . On the other hand, in the threaded hole shape shown in FIG.
It is possible to drive it out of 82.

As already mentioned with reference to FIG. 3, the cover assembly 7
A plurality of magnetic clip assemblies 104 are mounted on the hammerbank 18 to hold the upper portion of 8 fixedly relative to the hammerbank 18. One of those magnetic clip assemblies 104 is shown in detail in FIG. As shown in the figure, the magnetic clip assembly 104 includes a pair of pins 326 and 328 which are secured to the top 261 of the hammerbank 18 at separate locations spaced longitudinally of the hammerbank 18. From there, they extend outwardly from each other in a substantially parallel manner. An elongated base clip 330 extends between the outer ends 336 and 338 of the pins 326 and 328, respectively, the base clip 330 having both ends 332 and 334 at the pin outer ends 336, 338. Is fastened to. Each end 332, 334 of the base clip 330, when connected to that end, has outer ends 336, 33 of the pins 326, 328.
8 is partially wrapped around and is fixed by welding. A permanent magnet 340 is placed on an intermediate portion 342 between the both ends 332 and 334 of the base clip 330. The permanent magnet 340 is fixed to the middle portion 342 of the base clip 330 with three rivets, and these rivets are the top clip 346 and the permanent magnet 34.
0, and extends through the middle portion 342 of the base clip.

Mount the pins 326 and 328 to the top 261 of the hammerbank 18 and attach the magnetic clip assembly 1 as shown.
After assembling the remaining parts of 04, the plurality of magnet type clip assemblies 104 arranged on the top portion 261 of the hammerbank 18 at intervals in the longitudinal direction are subjected to the necessary grinding work, thereby each The clip assembly 104 will provide the reference surface 348 in the desired relative position to the top 261 of the hammerbank 18.
The reference surface 348 includes the outer ends of the pins 326 and 328, the edge of the base clip 330, the side edge of the permanent magnet 340, and the edge of the top clip 346. The upper edge 102 of the cover assembly 78 abuts on the reference surface 348, and the upper edge 102 of the cover assembly 78 is
It is defined by the reference plane 348. It is held in a desired relative position with respect to the hammerbank 18.

In this embodiment, six magnet type clip assemblies 104 are arranged on the top 261 of the hammerbank 18 at intervals along the length of the top. One of these magnetic clip assemblies 104 is shown in cross section in FIG. Further, in this embodiment, the permanent magnet 340 is made of a rubber magnet that can be magnetized. After assembling and grinding the magnetic clip assembly 104, the rubber magnet is magnetized to form the permanent magnet 340.

[Advantages of the Invention] Since the present invention is configured as described above, it has the effects described below.

In a printer in which an elongated hammer bank is reciprocally mounted inside an elongated frame structure and a plurality of magnetic coils are mounted on the hammer bank, the hammer bank is provided with an air cooling system. . In this air cooling system, pressurized air is introduced into a chamber inside the frame structure. The air introduced into the chamber is guided from the chamber to the surroundings of the magnetic coil through a plurality of openings formed in the hammerbank. This provides effective magnetic coil and hammerbank cooling.

A plurality of hammer springs can be mounted on the hammer bank, and a first high pressure chamber can be formed below the magnetic coil in a region between the hammer spring and the hammer bank. The plurality of openings of the hammerbank may include a first plurality of openings and a second plurality of openings, the first plurality of openings extending substantially vertically between the bottom of the hammerbank and the first high pressure chamber. Then, the second plurality of openings extend substantially horizontally between the rear surface of the hammerbank and the first high pressure chamber. Furthermore, the first plurality of openings and the second plurality of openings can be arranged alternately along the longitudinal direction of the hammerbank. With such a structure, the velocity of the air inside the first high-pressure chamber is increased, and at the same time, a considerable turbulent state is generated in the air.
The cooling effect of the magnetic coil located in the upper part of the high pressure chamber can be further enhanced.

Furthermore, the magnetic coil can be mounted on a bobbin with a large flange. The flange is located on the outer end of the bobbin and close to the moving part of the upper end of the hammer spring. The flanges of the respective bobbins are closely packed together and extend side by side, thereby forming an air dam. With this structure, most of the turbulent high-speed air inside the first high-pressure chamber leaks laterally through the gap between the adjacent hammer springs by the air dam. The air can be prevented. When leakage is prevented, the air is trapped substantially inside the first high pressure chamber and flows there upwards, around the magnetic coil, thereby providing the desired cooling effect.

Further, a plurality of pairs of magnetic pole pieces are mounted on a hammer bank, the magnetic coil is mounted on the magnetic pole pieces, and a permanent magnet is arranged between the magnetic pole pieces of each pair of magnetic pole pieces. You can With this structure, magnetic circuits that are essentially independent of each other can be formed, and the magnetic interaction between the pair of adjacent pole pieces is reduced.

Further, the permanent magnet may be a common member shared by a plurality of pairs of magnetic pole pieces. With this structure, the portion where the permanent magnet is present extends in the space between the pair of pole pieces adjacent to each other. The presence of permanent magnets in this space has the effect of reducing the amount of leakage flux.

Further, the hammerbank comprises two separate elongate members that sandwich a single, integrally formed shaft between them, the single shaft including the ends of the hammerbank. The structure can be extended outward from the. With this structure, it is easy to mount the hammer bank in a reciprocating manner, and at the same time, the strength of the entire structure is improved by using a single shaft, and separate shafts are used for the hammer bank. Eliminates the need to attach adhesives on both ends. If the shaft has a hollow shape, the weight of the hammer bank can be reduced. Further, the hammerbank is placed by inserting both ends of the shaft into the bearings on both sides. However, by forming the shaft into a single integral shape, the hammerbank is placed. The shaft cores at both ends of the shaft can be surely brought into the coaxial state.

Further, a screw hole for mounting the hammer spring is formed so as to extend from the hammer spring mounting surface into the inside of the hammer spring, and its tip has a first plural opening of the first cooling port forming a part of the air cooling system. It can be connected to the inside of each of the openings. With this structure, both ends of each screw hole are opened, that is, one end is opened outside the hammer bank on the hammer spring mounting surface, and the other end is formed in the hammer bank. First
It opens to the inside of one of the plurality of openings. With this structure, a longer hammer spring mounting screw can be used, and a space can be provided such that the tip of the screw can be protruded into the first opening if necessary. In addition, it is possible to prevent foreign matters such as oil from accumulating inside the screw holes.

Additionally, the printer may include a cover assembly such that the upper portion of the cover assembly is secured to the hammerbank using a plurality of separate magnetic clip assemblies attached to the hammerbank. With this structure, there is no need to magnetize the entire hammer bank, or substantially the entire hammer bank.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of main components of a printer including a shuttle assembly having an improved hammer bank according to the present invention, and FIG. 2 is a perspective view of the components shown in FIG. FIG. 3 is a perspective view showing the ribbon deck of FIG. 1 and a paper feed drive mechanism. FIG. 3 is a cover assembly and an elongated body for accommodating the improved hammerbank shown in FIG. 1 inside the shuttle assembly shown in FIG. FIG. 4 is an exploded perspective view showing a platen having a shape; FIG. 4 is a partial sectional perspective view of the hammer bank shown in FIG. 1; and FIG. 5 is an elongated shuttle base of the shuttle assembly shown in FIG. FIG. 6 is a perspective view of the shuttle base of FIG. 5 mounted on the base support member shown in FIG. 1, with an air chamber and duct for supplying pressurized air; Fig. 7 is a front view of the shuttle assembly shown in Fig. 1, Fig. 8 is a top view of the shuttle assembly shown in Fig. 1, and Fig. 9 is shown in Fig. 1. Rear view of the shuttle assembly, FIG. 10 is a left side view of the shuttle assembly shown in FIG. 1, FIG. 11 is a right side view of the shuttle assembly shown in FIG. 1, and FIG. 1 is a plan view of the shuttle assembly shown in FIG. 1, FIG. 13 is a plan view of the shuttle assembly shown in FIG.
FIG. 13 is a cross-sectional view taken along line 13-13 of FIG. 8, FIG. 14 is a perspective view of a small portion of the hammerbank shown in FIG. 1, showing a first high pressure of air according to the improved air cooling system. FIG. 15 is a cross-sectional view of the shuttle assembly of FIG. 1 taken along line 15-15 of FIG. 7, illustrating the manner of inflow into the chamber. FIG. FIG. 16 is a view for explaining a mode of sealing both ends of the hammer bank shown in FIG. 16, and FIG. 16 is a view showing four pairs of four forming a main part of the four magnet type hammer actuators mounted on the hammer bank shown in FIG. FIG. 17 is a front view of a pair of individual pole pieces and a common permanent magnet shared by the pair of pole pieces, and FIG. 17 is a front view of the four pairs of pole pieces and the common permanent magnet having the structure of FIG. Yes, explain that the magnetic flux leakage is limited by the presence of this permanent magnet. FIG. 18 is a cross-sectional view of a part of the hammer bank shown in FIG. 1, which is a view for explaining the structure of the improved screw hole for mounting the hammer spring according to the present invention, and FIG. A perspective view of a magnetic clip assembly according to the invention for fastening the upper part of the cover assembly in a fixed manner relative to the upper part of the hammerbank shown in FIG. FIG. 20 shows a bobbin flange which forms part of a magnet type hammer actuator and is shaped to form an air dam for an improved air cooling system,
21 is a side view of the magnetic coil assembly shown in FIG. 20. FIG. In the figure, 10 ... Shuttle assembly, 12 ... Printer, 14 ... Base support member, 18 ... Hammer bank, 20 ... Air chamber, 22 ... Duct, 24 ... Blower, 26 ... Shuttle base , 78 ... Cover assembly, 82 ... Shaft, 104 ... Magnet type clip assembly, 116 ... Hammer spring, 118 ... Hammer spring mounting surface, 120 ... Hammer spring mounting screw, 126, 128 ... Magnetic pole piece, 130 ... Groove, 132 ... Permanent magnet of magnet type hammer actuator, 134 ... Magnetic coil assembly, 136, 138 ... Magnetic coil, 282 ... First multiple opening, 284 ... Second multiple opening, 288: first high pressure chamber, 272: cavity forming a common high pressure chamber, 292: second high pressure chamber Chamber, 302, 304 ... Bobbin of magnetic coil, 306, 308 ... Flange of bobbin of magnetic coil, 324 ... Screw hole for mounting hammer spring, 326, 328 ... Pin of magnet type clip assembly, 330 ... Base clip of magnet type clip assembly, 340 ... Permanent magnet of magnet type clip assembly.

Claims (12)

[Claims] 1. An elongated frame structure mounted inside a printer and having an elongated chamber therein; and an elongated frame structure mounted on the inside of the elongated chamber of the frame structure. A slender hammerbank that can be reciprocally moved inside, including a plurality of magnetic coils mounted on the hammerbank along its longitudinal direction, a pressure air source, and the pressure air source. Means for connecting pressure air to the interior of the elongated structure chamber of the frame structure, the elongated shape hammerbank further forcing the pressure air from the chamber to the periphery of the plurality of coils A plurality of openings formed in the hammerbank, each of which has one end inside the chamber and the other end at the plurality of coils. A printer in the vicinity of the printer. 2. The elongated hammerbank includes a plurality of hammersprings, the hammersprings being mounted at the base of the hammerbanks along the longitudinal direction thereof and having an upper end opposite to the base. The hammer bank has a recess extending in the longitudinal direction of the hammer bank in the vicinity of the upper ends of the plurality of hammer springs, and the plurality of magnetic coils of the plurality of hammer springs. Extending into the recess of the hammerbank toward the upper end, the hammerbank having an elongate chamber having a lower region and formed therein, the elongate chamber comprising:
It extends in the longitudinal direction of the hammer bank and is arranged between the upper portion of the lower region of the hammer bank and the recess, and the plurality of openings are provided in the hammer bank along the longitudinal direction thereof. A plurality of first openings, which are arranged at intervals and extend substantially vertically between the lower region of the hammer bank and the recess of the hammer bank, and in the longitudinal direction of the hammer bank. A second plurality of openings spaced along and extending substantially horizontally from the upper portion of the lower region of the hammerbank through the elongated chamber to the recess. The printer according to claim 1, wherein the printer comprises: 3. An elongated frame made of a non-magnetic material, and a plurality of hammer springs mounted on the elongated frame along a longitudinal direction thereof, the hammer springs being mounted at a first end thereof. A plurality of hammer springs, wherein the first end is an end opposite to the second end, which is a free end, and a plurality of pairs of magnetic pole pieces mounted along the longitudinal direction on the elongated frame. Where each pair of the magnetic pole pieces is arranged in proximity to the second end which is the free end of the individual hammer spring of the plurality of hammer springs, and among each pair of the magnetic pole pieces A plurality of pairs of magnetic pole pieces on which a coil is mounted on at least one of the magnetic pole pieces, and a substantially continuous permanent magnet structure of an elongated shape, which extends along the longitudinal direction of the frame, A plurality of pairs of magnetic pole pieces; A substantially continuous permanent magnet structure disposed between and reducing the leakage flux between the pole pieces of each pair of pole pieces, and the pressure introduced into the elongated chamber. A printer hammerbank comprising: a plurality of openings for guiding pressurized air from an air source through the chamber to the periphery of the coil, one end of which is inside the chamber and the other end of which is near the coil. . 4. The substantially continuous permanent magnet structure comprises a plurality of permanent magnets mounted end to end in contact with each other, each of the permanent magnets comprising a plurality of pairs of pole pieces. Between the pair of magnetic pole pieces and the magnetic pole pieces of the pair of magnetic pole pieces, the rear end portions of the magnetic pole pieces and the magnetic pole pieces are arranged to be one of the plurality of permanent magnets. They are arranged on the opposite side of the permanent magnet and extend so that their front ends, which are opposite to the rear end, abut the second end, which is the free end of one of the hammer springs. 4. The hammer bank for a printer according to claim 3, wherein the hammer bank is exposed and a coil is mounted on the end portion. 5. An elongated hammerbank frame, a plurality of hammerbank frames mounted on the frame along a longitudinal direction of the frame, each of which is associated with one of the plurality of hammersprings. A magnetic hammer actuator and a single, hollow, non-separable shaft mounted inside the frame, extending in the longitudinal direction of the frame and extending outward from both ends of the frame. A hammer bank for printers, consisting of a shaft for reciprocally mounting a hammer bank. 6. The hammer bank for a printer according to claim 5, wherein the shaft is a shaft having a hollow cylindrical cross section. 7. An elongated frame, wherein a hammer spring mounting surface extending in the longitudinal direction of the frame and a plurality of openings formed in the frame at intervals along the longitudinal direction of the frame. And a plurality of screw holes formed in the frame at intervals in the longitudinal direction of the frame,
A frame each having the hammer spring mounting surface and a threaded hole extending from one of the plurality of openings; and a plurality of frames mounted on the frame along the hammer spring mounting surface. A hammer spring, each of which is mounted via a screw that penetrates the hammer spring and is screwed into the inside of each of the screw holes; 8. The plurality of openings are arranged substantially vertically, and further function to allow pressurized air to flow from outside the frame through the plurality of openings to an area on the opposite side of the frame. The hammer bank for a printer according to claim 7, wherein: 9. An elongated hammerbank mounted reciprocally, a cover assembly mounted on the hammerbank, and a hammerbank for holding the cover assembly on the hammerbank. A plurality of mounted magnetic clip assemblies, each of which includes a permanent magnet extending outwardly from the hammerbank,
A plurality of magnetic clip assemblies, wherein the permanent magnets rest on the clip assembly and hold a portion of the cover assembly to the permanent magnets by magnetic attraction. 10. A pair of pins, each of which is fixed to the hammer bank and extends outward from the hammer bank, and each of the magnet type clip assemblies extends between the pair of pins, and both ends thereof are formed by the two ends. 10. The printer according to claim 9, further comprising a base clip fixed to the pair of pins, and a permanent magnet mounted on an intermediate portion between both ends of the base clip. 11. Cooling air is introduced into an area in the vicinity of a plurality of coils connected to a hammer bank, and the area is disposed in the vicinity of the hammer bank and the coil mounted on the hammer bank. A plurality of hammer springs, in a hammer bank, in the vicinity of the hammer springs, at the end of the coil,
A plurality of bobbin flanges, the bobbin flanges extending outward from the coil so as to be continuous with each other, and passing between the hammer spring and the hammer bank to flow around the coil; A hammer bank featuring a combination of forming an air dam for air. 12. The coil is mounted on a pole piece,
The pole pieces extend outwardly from the hammerbank in pairs, and the polepiece pairs are spaced apart from adjacent polepiece pairs in the longitudinal direction of the hammerbank so that the pole pieces are spaced apart from each other. Forming a first pole piece row and a second pole piece row along the longitudinal direction of the hammer bank, and mounting the first coil row and the second coil row on these pole piece rows. So that the bobbin flanges of each coil row of these first coil row and second coil row are closely packed with the bobbin flanges of adjacent coils on both sides in the same row,
The hammer bank according to claim 11, wherein the hammer bank is extended so as to be closely packed with the bobbin flanges of the coils facing each other in another row.