JP2010272322A - Push button switch of electronic endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a push-button switch which is operated even when diagonally pushed and in which water-tightness is improved. <P>SOLUTION: In the push-button switch equipped with a hollow guide cylinder water-tightly fitted and fixed to a through-hole installed at a casing of an operation part of an endoscope, a movable pressurizing member which is displaced in the guide cylinder, a switch part which is installed at the lower part in the guide cylinder and abutted on the movable pressurizing member, and a button cover to cover the guide cylinder and the outside of the movable pressurizing member, a tapered flange part is installed at either one of the movable pressurizing member or the guide cylinder, an annular recess part into which an O-ring is fitted is installed at the other one of the movable pressurizing member or the guide cylinder opposing to the flange part, and the O-ring is water-tightly abutted on the annular recess part and the tapered flange part. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a push button switch provided in an operation unit body of an electronic endoscope.

  In a flexible endoscope with a curved distal end, an object in the body cavity of a patient is observed by operating a push button switch provided on the operation unit body while grasping the operation unit body of the endoscope. Or imaging an object.

  As a push button switch provided in the operation part main body of such an endoscope, a structure like patent document 1 is used. FIG. 1 shows a schematic diagram of the push button switch. The push button switch includes a hollow cylindrical guide cylinder 2 fitted and fixed in a through-hole provided in the casing 1 of the operation unit body of the endoscope, and a movable press that slidably moves in the guide cylinder 2. A member 3, a tact switch 4 below the movable pressing member 3 and performing an on / off operation in accordance with the pressing operation of the movable pressing member 3, and a head of the movable pressing member 3 and a casing of the operation unit main body And an elastic button cover 5 made of silicon rubber, fluorine rubber or the like covering the outer peripheral surface of the guide cylinder 2 protruding from 1.

  Furthermore, an annular recess 2a is provided on the outer peripheral surface of the guide cylinder 2 and facing the casing 1 of the operation portion main body over the entire periphery. An O-ring 6 is fitted over the entire circumference between the annular recess 2a and the casing 1 of the operation unit body, and the O-ring 6 is always connected to the annular recess 2a and the casing 1 of the operation unit body. It is in pressure contact. Therefore, the watertightness between the guide cylinder 2 and the casing 1 of the operation unit main body is ensured. Accordingly, even when the endoscope is subjected to a treatment such as cleaning or disinfection, liquid such as cleaning liquid or disinfecting liquid can pass through the gap between the end of the elastic button cover 5 and the through hole provided in the casing 1 of the operation unit main body. There is no intrusion into the operation unit body.

  A spring pressure is set on the tact switch 4, and the tact switch 4 supports the movable pressing member 3 when the operator does not operate the push button switch. When the surgeon pushes the elastic button cover 5 and the movable pressing member 3 is pushed down and a predetermined pressing force is applied to the tact switch 4, the tact switch 4 is turned on. The tact switch 4 is accommodated in a switch receiving frame 7 provided in the lower part of the guide cylinder 2, and an electrode portion 8 of the tact switch 4 extends on the lower surface side of the switch receiving frame 7. A wiring 9 is soldered to the electrode portion 8, and an on / off signal of the tact switch 4 is transmitted through the wiring 9 to a switch signal input circuit (not shown) in the operation unit main body.

  The switch receiving frame 7 is formed by screwing a switch retaining ring 10 into a female thread threaded on the inner periphery of the lower end of the guide cylinder 2, and pushing the switch receiving frame 7 toward the movable pressing member 3 by the switch retaining ring 10. The front end abuts on the step portion of the guide cylinder 2 and is fixed to the lower part in the guide cylinder 2. Further, the guide cylinder 2 is fixed to the casing 1 of the operation portion main body by a guide cylinder retaining ring 11. That is, when the internal thread formed on the inner peripheral surface of the guide cylinder retaining ring 11 is screwed with the external thread formed on the outer peripheral surface of the lower end portion of the guide cylinder 2 protruding into the casing 1, the guide cylinder 2 is moved to the casing. It can be prevented from falling to 1. The lower surface of the switch receiving frame 7 is filled with an insulating adhesive so as to cover the soldered portion of the electrode portion 8 and the wiring 9, and the tact switch 4 is fixed to the switch receiving frame 7 by this adhesive. .

  However, in such a push button switch, since the movable pressing member 3 can slide only in the axial direction relative to the guide cylinder 2, when the pressing force is applied from a direction other than the axial direction, such as obliquely or laterally, Since the switch may not function normally or a large pressing force may be required, the operability may be reduced. Therefore, a structure as disclosed in Patent Document 2 has been proposed as a push button switch that has an improved structure that is weak against oblique pressing.

JP 2002-170453 A Japanese Patent No. 3181657

  However, the conventional push button switch structure described in Patent Document 2 has the following problems. In other words, when the elastic button cover is torn, the endoscope is exposed to water vapor or immersed in water or chemicals to perform sterilization such as autoclave sterilization, or while the operator is wet. In such a case, the operation unit main body or the body cavity insertion unit may be submerged. For this reason, not only the cover but also the members in the operation unit main body and the body cavity insertion unit must be replaced, which increases the repair cost.

  The present invention has been made in view of the above circumstances. It is an object of the present invention to operate a push button switch even when a pressing force is applied from any one of a vertical direction, an oblique direction, and a horizontal direction, and even if the elastic button cover is broken, It is to provide a push button switch that can secure the property and prevent flooding.

  According to one embodiment of the present invention, a hollow guide cylinder that is fitted and fixed in a watertight manner to a through hole provided in a casing of an operation portion of an endoscope, and a movable pressing member that is displaced in the guide cylinder. A push button switch provided at a lower portion in the guide cylinder and in contact with the movable pressing member; and a button cover that covers the guide cylinder and the outer side of the movable pressing member. Either one is provided with a tapered flange portion, and an annular recess into which an O-ring is fitted is provided on either the movable pressing member or the guide cylinder facing the flange portion, and the O-ring has an annular recess and a tapered shape. It is in watertight contact with the flange portion. Thereby, the water tightness in the operation portion can be ensured by the O-ring, and further, a gap is formed in a portion where the O-ring is not in contact between the movable pressing member and the guide cylinder. Even in the case of lateral pressing, the movable pressing member can be tilted and displaced downward to depress the tact switch and operate the push button switch.

  Other embodiments of the present invention include an aspect in which the surface of the movable pressing member that contacts the switch part is a spherical surface, an aspect in which the O-ring is baked into an annular recess, and an aspect in which the O-ring is a D-ring. Can be mentioned.

  Furthermore, according to another embodiment of the present invention, when a pressing force in a direction other than the axial direction of the guide cylinder is applied to the movable pressing member via the button cover between the movable pressing member and the guide cylinder. The movable pressing member has a gap that allows the switch portion to operate by tilting obliquely.

  According to the structure of the push button switch of the present invention, since the O-ring is always in contact with the tapered flange portion of the movable pressing member, even if the switch is disposed in the guide cylinder, it is installed in the operation portion in advance. Watertightness can be secured even in the structure. In addition, since the O-ring suppresses the movable pressing member from tilting beyond a certain angle and generates a force that pushes down the switch, it is possible to press the switch with a small force from any direction. It is possible to improve the indentation performance.

It is a schematic sectional drawing which shows the structure of the conventional pushbutton switch. It is the schematic which shows the whole endoscope provided with the pushbutton switch in one Embodiment of this invention. It is a schematic sectional drawing which shows the structure of the pushbutton switch in one Embodiment of this invention. (A) And (b) is a schematic sectional drawing which shows operation | movement of the pushbutton switch in one Embodiment of this invention. (A), (b), (c) and (d) is a schematic sectional drawing which shows the structure of the pushbutton switch in other embodiment of this invention.

  Hereinafter, the structure of a push button switch in an embodiment of the present invention will be described with reference to the drawings. In addition, the same number is attached | subjected, when showing the same member over several figures.

  FIG. 2 is a schematic view showing an entire endoscope incorporating the push button switch of the present invention. As shown in FIG. 2, the endoscope has a flexible insertion portion 20 that is inserted into a body cavity of a patient, and an operation portion 21 is provided at the proximal end portion of the insertion portion 20. The operation section 21 is provided with a treatment instrument inlet section 24, an angle knob 25, and push button switches 26-30. The treatment instrument inlet section 24 communicates with a treatment instrument outlet section (not shown) provided at the distal end of the insertion section 20. The surgeon inserts a treatment tool such as forceps from the treatment tool inlet portion 24, takes out the treatment tool outlet through a treatment tool channel (not shown), and performs a treatment such as collecting tissue in the body cavity. The angle knob 25 bends the distal end region of the insertion portion 20 according to the turning operation. By operating the push button switches 26-30, air supply and water supply to the site to be observed, suction of body fluid, etc., freeze (freeze) of the screen on the TV monitor, switching of photometric pattern (average photometry and peak photometry), image recording Various processes such as recording of still images and moving images on a medium can be performed. The angle knob 25 and the push button switches 26 to 30 are respectively provided at positions where they can be operated by fingers of the hand holding the operation unit 21.

  The universal tube 22 is connected to an endoscope processor (not shown) via a connector 23. The universal tube 22 sends illumination light generated by a light source unit in the endoscope processor to the distal end portion of the insertion unit 20, and receives operation signals from the angle knob 25 and push button switches 26 to 30 in the endoscope processor. Or transmit to. When an imaging device is used as the observation mechanism, the universal tube 22 transmits a video signal from an imaging device (not shown) disposed at the distal end portion of the insertion portion 20 to the endoscope processor.

  FIG. 3 shows a schematic diagram of a push button switch according to an embodiment of the present invention. This push button switch can be used for each push button switch 26-30 shown in FIG. In FIG. 3, members other than the guide cylinder 2, the elastic button cover 5, the O-ring 12, and the movable pressing member 3 have the same structure as the conventional example. For this reason, the same members as those in the conventional example are denoted by the same reference numerals as those in FIG. 1 and description thereof is omitted here.

  As shown in FIG. 3, a taper-shaped flange portion 3 a is provided over the entire circumference of the lower end portion of the movable pressing member 3, and an O-ring 12 that contacts the flange portion 3 a is disposed between the movable pressing member 3 and the guide cylinder 2. It arranges in. An annular recess 2b is formed over the entire circumference of the inner peripheral surface of the guide cylinder 2 facing the flange portion 3a, and the O-ring 12 is fitted over the entire circumference of the annular recess 2b. Yes. The O-ring 12 is always in contact with the inner peripheral surface of the tapered flange portion 3a of the movable pressing member 3 and the annular recess portion 2b of the guide cylinder 2 in both the standby state and the pressing state of the push button switch. . Therefore, even if the elastic button cover 5 is torn, it will not be immersed in the operation unit main body. Further, since the flange portion 3a is formed in a tapered shape, the flange portion 3a is pressed by the O-ring 12 when the movable pressing member 3 moves in the vertical direction, that is, in a direction parallel to the axial direction of the guide cylinder 2. . If the movable pressing member 3 is a member that does not have a tapered flange portion as shown in FIG. 1, the movable pressing member 3 slides with respect to the O-ring 12. When a crack occurs, the O-ring 12 may not be able to ensure water tightness. According to the present embodiment, since the flange portion is tapered, the O-ring 12 does not slide while being in contact with the flange portion, and the water-tightness is ensured. Therefore, such a concern can be eliminated. .

  A concave portion is formed on the upper surface of the movable pressing member 3, and the concave portion is fitted with the convex portion of the elastic button cover 5. In a standby state where the operator does not apply a pressing force to the elastic button cover 5, the movable pressing member 3 is maintained in a state where the axial center direction thereof coincides with the axial center direction of the tact switch 4. A gap 13 a is formed between the outer peripheral surface of the upper end portion of the movable pressing member 3 and the inner peripheral surface of the head of the elastic button cover 5. In addition, a gap 13b is formed over substantially the entire circumference between the intermediate outer peripheral surface of the movable pressing member 3 and the inner peripheral surface of the guide cylinder 2. The gap 13b is continuous from the gap 13a and reaches the flange portion 3a. Here, the gap 13b is formed wider than the gap 13a. Specifically, the gap 13a formed in the vicinity of the upper end portion of the movable pressing member 3 is formed with a very small width so that the pressing force from the operator can be reliably transmitted. On the other hand, the gap 13b has a necessary and sufficient width so that the movable pressing member 3 functions as a play for balancing even when a pressing force other than the vertical direction is applied. Even if the operator's pressing force is applied obliquely to the elastic button cover 5 by the continuous gaps 13a and 13b, the movable pressing member 3 is pushed downward while being tilted somewhat, and the tact switch 4 is reliably operated. It becomes possible to make it.

  Further, a force in the vertical upward direction acts on the movable pressing member 3 due to the spring pressure of the tact switch 4, and a force in the vertical downward direction acts on the resultant force of the reaction force from the O-ring 12. As a result, the movable pressing member 3 always comes into contact with the tact switch 4, so that the tact switch 4 can be pressed without applying a large pressing force. Therefore, the surgeon can perform an operation without causing a hand shake when the push button switch is pressed in order to perform a freeze operation or the like during imaging of an object in the body cavity of the patient.

  Note that by adjusting the spring pressure in accordance with the function assigned to the push button switch, the pressing force required to operate the tact switch 4 can be changed. That is, not only can the tact switch be operated without applying a large pressing force as described above, but also the spring pressure can be increased to prevent the operation unless a large pressing force is applied.

  4A and 4B are diagrams showing a state where the push button switch is pushed vertically and a state where the push button switch is pushed obliquely. As shown in FIG. 4A, when the push button switch is pushed vertically, the movable pressing member 3 is in a state where the O-ring 12 is in contact with the upper end of the tapered flange portion 3a of the movable pressing member 3. Since the tact switch 4 is pushed down by moving downward in the guide cylinder 2, the water tightness by the O-ring 12 is not impaired. Further, as shown in FIG. 4B, when the push button switch is pushed obliquely, the repulsion from the O-ring 12 occurs when the angle formed by the surgeon's finger and the vertical direction becomes a certain angle or more. The magnitude of the force exceeds the magnitude of the pressing force from the finger. Therefore, the movable pressing member 3 does not tilt beyond a certain angle, and the repulsive force can be used as a force for pushing down the tact switch 4. For this reason, the push button switch can be operated with a small force. Furthermore, even in the case of oblique pressing, the state in which the O-ring 12 is in contact with the tapered flange portion 3a of the movable pressing member 3 is maintained, so that watertightness can be maintained. Also, in the case of lateral pressing, since the magnitude of the repulsive force from the O-ring 12 exceeds the magnitude of the pressing force from the finger, the repulsive force is used for the force that pushes down the tact switch 4 as in the case of the diagonal push. The push button switch can be operated.

  5 (a), (b), (c) and (d) are diagrams showing other various embodiments of the present invention. As shown in FIG. 5A, the lower surface of the movable pressing member 3 that contacts the tact switch 4 may be a spherical surface instead of a flat surface. In this configuration, the tact switch 4 can be always pushed down with a constant surface pressure regardless of the vertical pressing, the diagonal pressing, or the like, so that the tact switch 4 can be pressed without impairing operability without applying an abnormal load. A button switch can be operated. Particularly, when the structure is shown in FIG. 5A at the time of oblique pressing, the movable pressing member 3 can be smoothly inclined, and the repulsive force of the O-ring 12 can be efficiently changed to a force for pressing the movable pressing member 3. . Further, the repulsive force of the O-ring 12 can be used to smoothly return the movable pressing member 3 from the inclined position to the standby state after the finger is released from the elastic button cover 5.

  Further, as shown in FIG. 5B, the O-ring 12 and the tact switch 4 can be arranged in the operation unit main body with the positional relationship of the O-rings 6 and 12 reversed upside down. In this embodiment, the electrode portion 8 of the tact switch 4 is attached to the base plate 14 in the operation portion main body with an insulating adhesive. In addition, this configuration can reduce the height of the elastic button cover 5 and is suitable for a short push button switch. Further, since the tact switch 4 is located outside the guide cylinder 2, it is not necessary to incorporate the tact switch 4 into the guide cylinder 2 when manufacturing the push button switch, thereby simplifying the manufacturing process and reducing the manufacturing cost. You can also.

  Further, as shown in FIG. 5C, the member used for the O-ring 12 is not limited to the O-ring, but may be a D-ring, or may be baked on the guide cylinder 2 by performing a lining process. Thereby, since the member used for O-ring 12 at the time of manufacture of a pushbutton switch can be previously built into guide cylinder 2, more efficient manufacture is realizable. Furthermore, since the member used for the O-ring 12 is in close contact with the guide cylinder 2, the watertightness of the push button switch can be further enhanced.

  In the embodiment described above, the tapered flange portion 3a that contacts the O-ring 12 is provided on the movable pressing member 3 side. However, as shown in FIG. The recessed portion 16 is provided, the O-ring 12 is fitted into the annular recessed portion, and an inclined portion 17 is provided which expands toward the inner peripheral surface of the guide cylinder 2 so that the O-ring 12 contacts the inclined portion 17. Thus, water tightness can be secured while the movable pressing member 3 is in contact with the tact switch 4.

  As described above, by using the above-described configuration, it is possible to operate even in the case of an oblique push or a lateral push, and even if the button cover is torn, the water tightness that can prevent water from entering the operation unit has been improved. A push button switch can be provided.

DESCRIPTION OF SYMBOLS 1 Casing of operation part main body 2 Guide cylinder 3 Movable press member 4 Tact switch 5 Elastic button cover 6, 12 O-ring

Claims (5)

A hollow guide cylinder fitted and fixed in a watertight manner to a through-hole provided in a casing of an operation portion of the endoscope, a movable pressing member that displaces in the guide cylinder, and a lower portion in the guide cylinder. In a push button switch comprising a switch portion that contacts the movable pressing member, and a button cover that covers the guide cylinder and the outside of the movable pressing member,
A tapered flange portion is provided on one of the movable pressing member and the guide cylinder, and an annular recess in which an O-ring is fitted on either the movable pressing member or the guide cylinder facing the flange portion. Provided,
The push button switch, wherein the O-ring is in watertight contact with the annular recess and the tapered flange portion.   The push button switch according to claim 1, wherein a surface of the movable pressing member that comes into contact with the switch portion is a spherical surface.   The push button switch according to claim 1 or 2, wherein the O-ring is baked into the annular recess.   The push button switch according to any one of claims 1 to 3, wherein the O-ring is a D-ring.   When a pressing force in a direction other than the axial direction of the guide cylinder is applied to the movable pressing member via a button cover between the movable pressing member and the guide cylinder, the movable pressing member is inclined obliquely and the The push button switch according to any one of claims 1 to 4, further comprising a gap for operating the switch unit.

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