JPS649947B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanical printer in which noise during printing is improved.

2. Description of the Related Art Conventionally, wire dot printers, for example, have been known as printers for printing on various devices such as teletypes.

This wire dot printer is equipped with a head on which dot wires are arranged in a matrix, and this head is swept across the platen (printing surface element) to selectively pass the dot wires through an ink ribbon. Desired characters are printed by impacting the printing surface elements.

Although such a printing type wire dot printer has the advantage of being capable of high-speed and clear printing, it has the disadvantage of generating quite a lot of noise during printing operation.

As described above, various types of mechanical printers that print by impact have the drawback that vibrations occur due to the impact in the parts involved in the printing operation during the printing operation, and noise is generated accordingly.

The present invention was made in order to prevent printing noise in various mechanical printers that print by impact, and the parts involved in the above-mentioned impact operation include a twin boundary between a martensite phase or a parent phase and a martensite phase. This problem was solved by using an alloy with a crystal structure that has an inherent phase boundary.

Next, an alloy having a crystal structure including a twin boundary of a martensitic phase or a phase boundary between a parent phase and a martensitic phase will be explained using FIG. 3, which shows the atomic arrangement two-dimensionally. In addition, in the same figure,
White and black circles indicate different atoms.

An alloy with a crystal structure that includes a twin boundary of a martensitic phase or a phase boundary between a parent phase and a martensitic phase is a low-temperature phase of an alloy that undergoes thermoelastic martensitic transformation. That is, an alloy that undergoes thermoelastic martensitic transformation has a parent phase (a in Figure 3) above the transformation temperature;
Martensitic phase below the transformation temperature (b in Figure 3)
becomes. The temperature at which the martensitic phase transforms into the matrix phase is called the martensitic reverse transformation temperature, and the temperature at which the matrix transforms into the martensitic phase is called the martensitic transformation temperature. The difference between the martensite transformation temperature and the martensite reverse transformation temperature is about several degrees Celsius to several tens of degrees Celsius.

An alloy that undergoes such a thermoelastic martensitic transformation has twin boundaries of the martensitic phase within the alloy (Fig. 3b) depending on the temperature below the transformation temperature.
) or a crystal structure containing a phase boundary between the parent phase and the martensitic phase (see d in Figure 3). Because it contains this twin boundary or boundary phase, it has the special property of being able to relax the energy of stress applied from the outside by moving the boundary.

For example, the atomic positions of the alloy in the martensitic phase are in a state in which a certain atomic plane is symmetrically displaced in a mirroring relationship, as shown in FIG. When external stress is applied in this state, some atoms move in parallel so that the jagged edges become straight, and energy is consumed so that they approach the deformed martensite structure as shown in c in Figure 3 (boundary movement). The occurrence of vibration is alleviated.

Furthermore, this alloy also has a property of high mechanical strength.

The present invention was made by focusing on the two excellent properties of an alloy (referred to as a low-temperature phase alloy) having a crystal structure that includes a twin boundary of the martensitic phase or a phase boundary between the parent phase and the martensitic phase (referred to as a low-temperature phase alloy). An embodiment thereof will be described below in detail with reference to the drawings.

FIG. 1 is a side view of essential parts of an embodiment of a printer according to the present invention. In the drawings, a dot wire 1 is a printing element and performs an impact operation between it and a corresponding printing surface element (not shown) such as a platen. 2 is an armature, 3 is a dot wire mounting portion, 4 is a holding plate, 5 is a yoke, 6 is an excitation winding, 7 is a driving electromagnet, 8 is a base, and 9 is a stopper for the armature. The dot wire 1 is connected to an armature 2 at a mounting portion 3, and the armature 2 is fixed to an end of a yoke 5 by a holding plate 4.

The armature 2 is attracted to the electromagnet 7 when the driving electromagnet 7 is energized, moves backward when the driving electromagnet 7 is de-energized, and its position is regulated by contacting the stopper 9.

The armature 2, dot wire mounting portion 3, holding plate 4, yoke 5, base 8, and stopper 9 are connected to the printing element by the action of the drive winding 6 and drive electromagnet 7, which are drive sources. Stamping mechanisms are well known that provide an impact action between the printing surface element and the printing surface element.

Noise is generated during printing due to rapid changes in the momentum of each component involved in the impact motion of the dot wire 1. In other words, the dot wire 1 collides with the printed surface, and the electromagnet 7 of the armature 2
Noise is generated when the armature 2 collides with the stopper 9, etc. In addition, when the armature 2 performs an impact operation, the electromagnet 7
and the position of collision with the stopper 9.

In this embodiment, some or all of the dot wire 1, armature 2, mounting part 3, presser plate 4, yoke 5, stopper 9, and base 8 are made of the above-mentioned low-temperature phase alloy (i.e., The alloy undergoes thermoelastic martensitic transformation at a temperature below the transformation temperature. The above part includes some parts and some parts. The parts formed using the above-mentioned low-temperature phase alloy include parts that do not perform direct collision operations, but this also applies when the above-mentioned low-temperature phase alloy is used for parts that indirectly support the collision of dot wires, etc. This is due to the reduction of noise during a collision.

When external stress is applied to a component made of a low-temperature phase alloy, the stress energy becomes internal frictional heat within the alloy and is greatly alleviated. The generation of vibration noise is alleviated.

The following are examples of alloys that undergo thermoelastic martensitic transformation and are suitable for achieving this effect.

Ti-Ni (49~51atomic%Ni) Cu-Al-Ni (14~14.5weight%Al, 3~
4.5weight%Ni) Cu―Zn―Al (several atomic%Al) Mn―Cu―Al―Fe―Ni (54atomic%Mn,
37atomic%Cu, 4atomic%Al, 3atomic%
Fe, 2atomic%Ni) Mu-Al-Cu (40~45atomic%Mn, 1.4~
2.25 atomic% Al, Cu) Select one with the desired transformation temperature from among these.

Further, a characteristic diagram of an alloy that undergoes thermoelastic martensitic transformation is shown in FIG. 2, and it can be clearly seen that it has excellent mechanical strength and vibration damping properties compared to other metals.

As explained above, according to the present invention, at least a part of the member, printing element, or printing surface element that is displaced to perform an impact operation in the marking mechanism is formed by a twin boundary or matrix of the martensitic phase. By forming an alloy with a crystalline structure that has a phase boundary between the phase and the martensitic phase, noise reduction can be achieved even in mechanical printers.

[Brief explanation of the drawing]

Figure 1: A side view of essential parts of an embodiment of a printer according to the present invention, Figure 2: An alloy that undergoes thermoelastic martensitic transformation (referred to as thermoelastic martensitic alloy in the drawings). Characteristic diagram, Figure 3:
FIG. 2 is an explanatory diagram two-dimensionally showing the state of atomic arrangement in an alloy that undergoes thermoelastic martensitic transformation. Code, 1: wire, 2: armature, 5:
Yoke, 6: Excitation winding, 7: Driving electromagnet, 9:
Stopper.

Claims (1)

[Claims] 1. A mechanical device having a printing element, a printing surface element that prints by impact with the printing element, and a printing mechanism that causes impact between the printing element and the printing surface element. In the printer, at least a part of the member of the stamping mechanism that is displaced to perform the impact operation, the printing element, or the printing surface element is connected to a twin boundary of a martensite phase or a parent phase and martensite. A printer characterized in that it is made of an alloy with a crystalline structure that includes phase boundaries.