JP2629714B2 - Printhead cooling mechanism - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a cooling mechanism for cooling a head for an impact dot printer.

(Prior Art) In the head of an impact dot printer, since the heat generated in the actuator portion cannot be ignored, the head is cooled by a fan disposed in the case of the printer or a fan incorporated in the head itself. .

Of these cooling mechanisms, the former mechanism is not so limited by the size of the mechanism itself, but depending on the arrangement position, the carriage frame or the like interposed between the head and the head obstructs the air passage and cools. Not only will the effect be impaired, but there is the disadvantage that the head is cooled only when the head is transferred to the vicinity of the fan, and the latter has the advantage of being able to cool the head no matter where it is, There is a problem that a sufficient cooling effect cannot be exerted due to severe restrictions on the size and weight.

(Problems to be Solved by the Invention) The present invention has been made in view of such a problem, and an object of the present invention is to provide a new print head cooling mechanism capable of exhibiting a compact and efficient cooling effect. Is to provide.

(Means for Solving the Problems) That is, according to the present invention, as a print head cooling mechanism for achieving the above objects, a print head formed by fixing a radiator having a centrifugal blower in the center to the back surface of the head is provided. A large number of radiating fins are installed on the bottom plate of the radiator so as to surround the blower, and radiating fins that also serve as wind shields are installed on both ends in the running direction of the bottom plate in a direction perpendicular to the running direction. It is something to do.

Embodiment An embodiment of the present invention will be described below.

FIG. 1 shows an embodiment of the present invention. In the impact dot head 1a, a radiator is provided on the back surface of the wire drive unit, that is, on the surface opposite to the nose of the wire drive unit.
2A, the radiator 2a is provided with an impeller 5a having radial blades at the center of a bottom plate 8a and a two-phase stepper driving the impeller 5a, as shown in FIG. A centrifugal blower 3a constituted by a motor 4a is provided, and a number of radiating fins 6 are provided around the centrifugal blower 3a.
a, 7a are erected on the bottom plate 8a in a direction orthogonal to the traveling direction, and furthermore, among these radiating fins 6a, 7a,
The radiation fins 7a located at both ends in the running direction of the head 8a
In order to prevent the air from flowing into the radiator 2a when the vehicle travels, the fins are configured as radiation fins which also serve as wind shields having a width substantially equal to the width of the bottom plate 8a.

The cooling mechanism configured as described above can reduce the size of the cooling mechanism as a whole because the two-phase stepping motor 4a to be used can be configured to be thin, and the radial shape of the blades of the impeller 5a makes this possible. Kind of motor 4a is CW,
Regardless of the direction of rotation in the CCW direction, the air drawn in from the rear in the center direction of the mechanism can be discharged to the outside through the space between the heat radiation fins 6a and 7a along the bottom plate 8a.

In addition, since the outlet of the air flow path formed between the radiation fins 6a and 7a opens along the traveling direction of the head 1a,
Since the dynamic pressure associated with the traveling of the head 1a has a function of extracting the internal air at this portion, the stepping motor 4a provided in the cooling mechanism can be further reduced in weight by adopting a smaller output.

FIG. 2 shows a second embodiment of the present invention, in which a radiator fixed to the rear surface of the head has an impeller disposed in the center.
A large number of radiating fins 6b, centering on the impeller 5b, are erected around the periphery of the bottom plate 5b, and both ends of the bottom plate in the running direction have a width equivalent to the width of the bottom plate. Radiating radiation fins 6b are used instead of radiation fins 7b
Are erected with a gap between them.

In this embodiment, the impeller 5a having radial blades discharges the air drawn toward the bottom plate from the rear of the center of the mechanism to the outside along the radiation fins 6a extending in the radial direction, thereby forming the head 1a. Cooling can be performed more effectively.

Further, in still another embodiment shown in FIG. 3, the tip of the blade of the impeller 5c attached to the shaft of the two-phase stepping motor 4c is extended so as to cover the motor 4c and close to the bottom plate 8c of the radiator. This allows the air drawn into the center to flow along the radiating fins 6c over the entire height of the centrifugal blower 3c to further enhance the cooling effect. It is something that you get.

(Effects) As described above, according to the present invention, a large number of radiating fins are erected around the centrifugal blower 3 disposed in the center of the radiator so as to surround the centrifugal blower 3. The radiating fins, which also function as wind shields, are set up in a direction perpendicular to the running direction, so that the air flowing into the radiator during running of the head is shut off, and the impeller is smoothly rotated even by a small torque stepping motor. By applying air drawn from the rear of the central part of the radiator to the bottom plate that is in close contact with the head, not only does the entire head cool uniformly and efficiently, but also as the head travels, it opens on both sides in the traveling direction of the radiator. This creates a negative pressure that draws out the internal air, reduces the load on the centrifugal blower, and enables the use of a smaller drive motor, making this type of cooling mechanism more compact. Can be configured.

In addition, when the centrifugal blower is constituted by an impeller having blades in the radial direction and a two-phase stepping motor for driving the impeller, not only can the cooling mechanism be configured more compactly, but also the rotation direction is constant. The required air blowing function can be exhibited without it.

[Brief description of the drawings]

1 (a) and 1 (b) are a side view and a front view showing a cross section of a cooling mechanism according to an embodiment of the present invention, and FIGS. 2 and 3 are other embodiments of the present invention. It is the front view and side view which showed. 1a, 1e Impact dot print head 2a, 2c Radiator 3a, 3b, 3c Centrifugal ventilation 4a, 4b, 4c Two-phase stepping motor 5a, 5b, 5c Impeller 6a, 6b 6c: Heat radiation fins 7a, 7b, 7c: Heat radiation fins 8a, 8c that also serve as wind shields

Claims (4)

(57) [Claims] A print head of a type in which a radiator having a centrifugal blower disposed in the center is fixed to the back of the head.
A large number of radiating fins are erected on the bottom plate of the radiator so as to surround the blower, and at both ends in the running direction of the bottom plate, the blower and the bottom plate to a portion where the large number of radiating fins are erected. A print head cooling mechanism characterized in that radiation fins, which also function as wind shields, are provided upright in a direction perpendicular to the traveling direction to prevent inflow of air due to traveling. 2. A centrifugal blower comprising: an impeller having a plurality of blades extending radially; and a two-phase stepping motor for driving the impeller. 2. The print head cooling mechanism according to claim 1. 3. A radiating fin other than the radiating fins at both ends in the running direction is provided upright around the centrifugal blower and in a direction perpendicular to the running direction. 6. The print head cooling mechanism according to claim 1. 4. The print according to claim 1, wherein a plurality of radiating fins other than the radiating fins at both ends in the traveling direction are erected radially around the centrifugal blower. Head cooling mechanism.