JPS5942969A - Printing head - Google Patents

Abstract

PURPOSE:To obtain a printing head whose spring force is easily regulated and controlled by using a system in which an attraction part is held on the polar face with a rotary fulcrum of an iron core by a screw to be inserted into a round hole at one end of a spring part provided to the attraction part, and the force of the spring part is adjusted. CONSTITUTION:An attraction part 2 is held on the polar face with a rotary fulcrum of an iron core 5a by a screw 8 with a small diameter shaft 8a to be inserted into a round hole 4a provided in one end of a plate spring 4, and the force of the spring 4 is adjusted. The contact portion between an interposition part 9 inserted between the plate spring 4 and the screw 8 and the plate spring 4 is matched with the center line of the plate spring 4 because the shape of the interposition part 9 is spherical. Since no distorsion deformation other than outside-face bending occurs in the plate spring 4, exact operation of the printing head can be attained without fine movement to left and right sides of the attraction part 2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a print head for an impact type printer, and in particular, the strain energy of a spring member stored by the attractive force of a permanent magnet is canceled by the magnetic flux of an electromagnet to cancel the attractive force of the permanent magnet. The present invention relates to a print head of a cancel type printer that applies suction to a suction member.

The print head of an impact printer generally biases a spring member using the attraction force of an electromagnet, stores strain energy in this spring member, and prints the strain energy of the spring member by releasing the attraction force of the electromagnet. There is a type that acts as an operating force, the so-called electromagnet drive type, and a type that biases a spring member by the attractive force of a permanent magnet and stores strain energy in this spring member, and the attractive force of the permanent magnet due to the magnetic flux of the electromagnet. There is a so-called cancellation type, in which the strain energy of a spring member acts as a printing operation force by canceling the .

The above-described cancel type print head has been widely used in recent years because it has various advantages over the electromagnetic drive type.

In this type of print head, the print wire and the suction member provided therewith are caused to fly by strain energy stored by the bias of the spring member.

That is, since the spring force of the spring member becomes the printing energy of the instant printing wire, the magnitude of the spring force of this spring member has a great influence on printing quality.

However, in conventional print heads of this type, one end of the spring member is fixedly supported. For this reason, the spring force of this spring member must be adjusted by the magnetic force of the permanent magnet or the excitation force of the electromagnet, and there is a problem in that it is very difficult to manage the adjustment.

The present invention has been made based on the above-mentioned problems, and an object of the present invention is to provide a print head in which the spring force of the spring member can be easily adjusted and managed.

In order to achieve the above object, the present invention provides a print head in which an attraction member is moved by magnetic attraction force, and strain energy obtained by biasing a spring member provided on the attraction member is used as an impact printing force. At the end of the spring member, a pushing member that holds the suction part completely and adjusts the spring force of the spring member is placed so that the rotation fulcrum is on the magnetic pole face of the yoke forming a magnetic circuit therebetween. engaged with;
An intermediate member is provided between the pushing member and the spring member.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the print head of the present invention. In the figure, 1 is a printing bottle, 2 is a suction member, 3 is a lever that connects the printing bottle and the suction member 2, 4 is a leaf spring provided on the suction member 2, and 5a.

5b is an iron core, 6 is a permanent magnet provided between the iron cores 5a and 5b, 7 is a coil equipped with the iron core 5alC, and 8 is a small diameter shaft inserted into the circular hole 4a provided at one end of the leaf spring 4. This screw rest 8 has the function of holding the suction member 2 so that it has a rotational fulcrum on the magnetic pole surface of the iron core 5a, and also fully adjusting the spring 4. Reference numeral 9 denotes an intermediate member inserted between the leaf spring 4 and the screw body 8. As shown in FIG. 2, this intermediate member 9 has a spherical surface on the leaf spring 4 side. Therefore, this intermediate intervening member 9
The contact area A between the leaf spring 4 and the leaf spring 4 is as shown in FIG.
It coincides with the center line of .

Next, the operation of the print head of the present invention described above will be explained.

Before printing starts, the attraction member 2 is attracted to the iron cores 5a and 5b by the attraction force of the permanent magnet 6. At this time, the leaf spring 4 bends and generates a restoring force. Here, by rotating the screw body 8, the spring force of the leaf spring 4 can be freely adjusted.

Next, when a current is applied to the coil 7 to cancel the magnetic flux of the permanent magnet 6, the attraction member 2 is rotated by the restoring force of the leaf spring 4. As a result, the character υ is printed on the printing paper by the printing bin.

Further, when the spring force is adjusted by the screw body 8, the intermediate member 9 comes into contact with the leaf spring 4 along the center line of the leaf spring 4, as shown in FIG. Therefore, the leaf spring 4 does not undergo any screw deformation other than out-of-plane bending. Therefore, the suction member 2 following the leaf spring 4 operates accurately without making slight movements from side to side.

Incidentally, in the above embodiment, the intermediate member 9'f: was provided so as to be movable in the radial direction with respect to the axis of the screw body 8;
It is also possible to fix it to Alternatively, the tip of the screw body 8 may be formed into a spherical surface as shown in FIG.

Further, due to a change in the deflection of the leaf spring 4 as the suction member 20 rotates, the positional relationship between the intermediate member 9 and the screw rest 8 changes, and these come into sliding contact and wear out. In order to prevent this wear, it is effective to maintain the contact area between the screw body 8 and the intermediate member 9 to a maximum. As a measure for this, it is preferable that the contact portion between the threaded body 8 and the intermediate member 9 be brought into spherical or conical contact as shown in FIGS. 5 and 6. With this configuration, the period for readjusting the spring force of the leaf spring, etc. is lengthened9, and maintainability is improved and its reliability is also improved.

As described in detail above, according to the present invention, the leaf spring is only subjected to bending deformation, so that the spring force can be set accurately. Therefore, spring force adjustment management can be performed reliably.

[Brief explanation of the drawing]

FIG. 1 is a side view of one embodiment of the print head of the present invention, and FIG.
The figure is a side view showing all the main parts in cross section of one embodiment of the print head of the present invention, FIG. FIG. 6 is a diagram showing another embodiment of the main part of one embodiment of the print head of the present invention. DESCRIPTION OF SYMBOLS 1... Printing pin, 2... Attraction member, 3... Lever, 4... Leaf spring, 5a, 5b... Iron core, 6... Permanent magnet, 7... Coil, 8 ...Screw body, 9...Intermediate intervening member. 1st mouth 7th solid = 301 3 Figure 40 City Figure 5 Figure 6

Claims (1)

[Scope of Claims] 1. In a print head in which a suction member is moved by magnetic attraction force, and the strain energy obtained by the deflection of a spring member provided on the suction member is used as an impact printing force, the suction member is A pushing member that holds the attraction member and adjusts the spring force of the spring member is engaged with the end of the spring member so that the rotation fulcrum is on the magnetic pole surface of the iron core that forms the entire magnetic circuit between them; A print head characterized in that an intermediate member is provided between the pushing member and the spring member. 2. The print head according to claim 1, wherein the surface of the intermediate member that contacts the spring member is formed into a spherical surface. 3. The print head according to claim 2, wherein the intermediate member and the pushing member are in contact with each other through a spherical surface. 4. The print head according to claim 2, wherein the intermediate intervening portion and the pushing member are in contact with each other through a conical surface.