WO2022130954A1

WO2022130954A1 - Handset for medical use

Info

Publication number: WO2022130954A1
Application number: PCT/JP2021/043660
Authority: WO
Inventors: 美沙松本; 克也宮川
Original assignee: ニプロ株式会社
Priority date: 2020-12-18
Filing date: 2021-11-29
Publication date: 2022-06-23
Also published as: JPWO2022130954A1

Abstract

Provided is a handset for medical use that has a novel structure and that can achieve, inter alia, an improvement in operability when an attachment for medical use such as a mounted shaft drill is turned in a direction substantially plumb downward.　This handset 14 for medical use comprises a housing 45 having an intermediate portion A that accommodates an electric motor 46, a frontward portion B that constitutes a tip grip section in a style that allows for holding in the same manner as a pen, and a rearward portion C that has a battery built-in, the handset 14 for medical use being such that a rotating output shaft 52 is provided on an input axis Z of an attachment 10 for medical use that is provided with an input shaft driven so as to rotate about one axis, the rotating output shaft 52 extending toward the frontward side from the rotational driving shaft of the electric motor 46, and the input shaft of the attachment 10 for medical use being coupled with the rotating output shaft 52.

Description

Medical handset

The present invention relates to a medical handset that exerts a rotational driving force around one axis with respect to a medical attachment that is actuated by a rotational driving force.

As a kind of medical device, there are various medical attachments that can be operated by applying a rotational driving force around one axis. For example, in spinal surgery under an endoscope, bones such as vertebrae are cut using a medical shaft drill that is inserted through a through hole in the lens barrel of a rigid endoscope. There is. Such a shaft drill has a long shaft portion so as to be inserted into a through hole in the lens barrel of the endoscope, and the drill head at the tip of the shaft protrudes from the lens barrel to the tip. ..

By the way, as a medical handset that exerts a rotational driving force around one axis on a medical attachment such as a shaft drill, for example, as shown in Japanese Patent Application Laid-Open No. 2020-81282 (Patent Document 1), electricity is used. Those using a motor as a drive source are known.

Further, Japanese Patent Application Laid-Open No. 2019-520860 (Patent Document 2) proposes a medical handset that does not require the handling of a power supply cord by incorporating a battery for driving an electric motor.

Japanese Unexamined Patent Publication No. 2020-81282 Special Table 2019-520860 Gazette

However, in the conventional medical handsets described in Patent Documents 1 and 2, there is a problem that it is difficult for the practitioner who grips the handpiece to exert a pushing force in the direction of the rotation axis.

That is, in the hand set described in Patent Document 1, a shaft drill is attached as a medical attachment and is rotationally driven. However, the rotational output shaft to which the shaft drill is attached is a handpiece that accommodates the rotational drive shaft of the motor. Since it is approximately orthogonal to the shaft, when an external force is applied to push (push off) or pull (pull off) the shaft drill in the direction of the axis of rotation by the hand holding the handpiece, the shaft is affected by the external force or reaction force. A rotational moment in the direction of tilting the drill is likely to occur. Therefore, it has been difficult to efficiently exert a pushing force and a pulling force in the direction of the drill rotation axis on the shaft drill with a sufficient magnitude.

Further, the handset described in Patent Document 2 is also a gun type having a grip portion protruding in a direction substantially orthogonal to the rotation output axis direction. Therefore, as with the hand set described in Patent Document 1, the operating force and reaction force of the handpiece tend to generate a rotational moment in the direction in which the shaft drill is tilted, and the drill is used for a shaft drill mounted as a medical attachment. It was difficult to apply a pushing force or a pulling force in the direction of the axis of rotation.

In particular, in the case of a long shaft drill such as a shaft drill used by being inserted into the barrel of a rigid endoscope, Patent Documents 1 and 2 in which the central axis of grip by the practitioner is substantially orthogonal to the rotation axis of the shaft drill. In a conventional handset as described, a small swing in the grip portion provided on the base end side of the shaft drill is greatly amplified at the tip portion (drill head) of the shaft drill, for example, a pushing force or a pushing force with respect to the shaft drill. It has also become clear that it is difficult to accurately position the drill head when performing cutting operations while exerting a pulling force.

Further, in the conventional hand set described in Patent Documents 1 and 2, a handpiece or a gun-type grip portion is provided so as to project in a direction substantially orthogonal to the rotation axis and accommodate the rotation drive axis of the motor. Therefore, when the medical attachment is operated substantially vertically downward, such as in endoscopic spinal surgery, the gravity exerted on the handpiece and the grip itself acts as a rotational moment that tilts the medical attachment. Resulting in. Therefore, it has become clear that the practitioner needs to adjust the operating force in order to eliminate the rotational moment, which makes the operation even more difficult.

In addition, in the conventional handset described in Patent Documents 1 and 2, since the portion protruding in the direction substantially orthogonal to the rotation axis is gripped, the rotation reaction of the medical attachment during cutting is performed. The force is received by only one grip portion that is off the rotating shaft for driving. Therefore, there is a possibility that the medical attachment may be shaken or the like, especially when the rotational reaction force fluctuates, and there is also a problem that it is difficult to stably hold the medical attachment during work such as cutting.

The problem to be solved by the present invention is to solve at least one of the problems inherent in the conventional handset for a medical handset that exerts a rotational driving force around one axis with respect to a medical attachment that is operated by the rotational driving force. Or to reduce it.

Hereinafter, preferred embodiments for grasping the present invention will be described, but each of the embodiments described below is described as an example, and not only can be appropriately combined with each other and adopted, but also described in each embodiment. The plurality of components of the above can be recognized and adopted independently as much as possible, and can be appropriately adopted in combination with any of the components described in another embodiment. Thereby, in the present invention, various other embodiments can be realized without being limited to the embodiments described below.

The first aspect is a medical handset to which a medical attachment is attached and exerts a rotational driving force around one axis with respect to the medical attachment, which includes an electric motor as a driving source. It is arranged coaxially with the rotation drive shaft of the above toward the front side, and the rotation drive shaft is connected to the rear end, and the input shaft of the medical attachment is connected to the tip. A shaft is provided, a battery is arranged on the rear side coaxially with the rotation drive shaft of the electric motor, and the electric motor, the rotation output shaft, and a housing containing the battery are provided. The housing extends from the intermediate portion toward the tip side with the same or smaller outer peripheral length in the front portion accommodating the rotational output shaft as compared with the intermediate portion accommodating the electric motor. The outer peripheral surface of the portion constitutes a fingertip gripping portion that the operator grips in a pen-holding style with a fingertip.

In the handset of this embodiment, for example, the following effects (1) to (8) can be exhibited.
(1) Since the rotation drive shaft of the electric motor and the rotation center axis of the shaft drill are arranged on the same axis, the rotation drive shaft of the motor and the rotation input shaft of the medical attachment are particularly as in Patent Document 1. Compared to the conventional structure in which the electric motors are substantially orthogonal to each other, it is possible to prevent the handset and thus the medical attachment from being shaken due to the rotational drive reaction force of the medical attachment by the electric motor.
(2) By arranging the electric motor and battery, which are particularly heavy parts in the handset, on the rotation input shaft of the medical attachment, the central axis of inertia in the rotation direction is brought closer to the rotation input shaft of the medical attachment, and medical treatment is performed. Axial shake due to the rotational drive reaction force of the attachment can be suppressed and rotational stability can be improved.
(3) By arranging a heavy battery at a position away from the rear end side of the housing with respect to the fingertip gripping portion (support point) provided on the front portion of the housing, the moment of inertia with respect to the tilt around the support point is provided. Can be increased. Therefore, even with a medical attachment such as a relatively long shaft drill, the resistance to tilting as an operation reaction force such as cutting can be efficiently expressed by skillfully using the battery, and treatment such as cutting can be performed. The position stability of the treatment head portion (drill head, etc.) of the medical attachment at times, and thus the cutting accuracy can be improved.
(4) By connecting the rotary output shaft to the rotary drive shaft of the electric motor, the housing is extended forward from the electric motor, and the outer peripheral length is reduced by the extended portion to grip it in a pen-holding style. It was possible to realize a shape suitable for.
(5) Since the front part of the housing can be gripped in a pen-holding style, it is easy to grip the housing when operating the medical attachment substantially vertically downward, for example, in endoscopic spinal surgery. , Operational stability and accuracy can be improved.
(6) The combination of gripping the housing in a pen-holding style and arranging the heavy electric motor and battery on the rotation input shaft of the medical attachment, for example, endoscopic plumb bob surgery, etc. When operating a medical attachment such as a shaft drill substantially vertically downward, the weight of the handset itself can be used as the pushing force or pushing pressure of the medical attachment in the rotational drive axis direction. , The operability can be improved.
(7) A portion having the same or larger outer peripheral length (intermediate portion accommodating an electric motor and rear portion accommodating a battery) is provided behind the front portion provided with a fingertip grip portion in a pen-holding style. As a result, the hand gripped by the pen-holding style can be prevented from shifting backward. Therefore, even in situations where the weight of a heavy electric motor or battery is directed downwards, such as when operating a medical attachment approximately vertically downwards, the housing should be firmly penned. It is possible to continue to hold the grip stably and easily with the holding style.
(8) When the medical attachment attached to the handset is long, such as a shaft drill inserted into the lens barrel of a rigid endoscope, the tip of the handset at which the medical attachment is attached. A fingertip grip portion is provided on the portion, and a position as close as possible to the tip of the medical attachment can be gripped. Therefore, it is possible to efficiently apply a force effective for suppressing the swinging or tilting of the medical attachment itself at the fingertip gripping portion.
It should be noted that the action and effect of the present invention are subjective, and the requirements differ depending on factors such as the usage conditions, usage conditions, and purpose of use of the handset. Therefore, in the present invention, at least of the above (1) to (8). It suffices if one action and effect is exhibited.
Further, in the medical handset according to the present invention, a medical attachment such as a shaft drill can be detachably attached to the rotary output shaft, and the handset can be replaced with a necessary or appropriate medical attachment as appropriate. It is desirable that it can be used. However, the present invention is also applicable to a medical handset in which a specific medical attachment is attached to a rotary output shaft in a fixed state or a state close to the fixed state.

The second aspect is the medical handset according to the first aspect, wherein a speed control switch for adjusting the rotation speed of the electric motor is provided on the outer peripheral surface of the fingertip grip portion. be.

In the handset of this embodiment, the speed control switch is arranged on the outer peripheral surface of the fingertip gripping portion set in the pen holding style set on the front part of the housing, so that the fingertip can be moved greatly while gripping in the pen holding style. Instead, the speed control operation can be easily realized with one fingertip such as a human pointing finger. Therefore, it is possible to easily control the rotational speed while suppressing the occurrence of unstable movements such as shaft shake and tilt in medical attachments such as shaft drills.

The third aspect is the medical handset according to the second aspect, in which the outer peripheral surface constituting the fingertip grip portion in the front portion has a rounded rectangular outer peripheral cross-sectional shape. The speed control switch is arranged so as to operate in the axial direction on the short side.

In the handset of this embodiment, the rounded rectangular outer peripheral cross-sectional shape makes it easier to specify the gripping direction while making the gripping with the fingertips even better. For example, it is possible to put a thumb on one long side part and hold it, and to operate the speed control switch arranged on the short side part with the index finger. This makes it possible to realize stable holding with the thumb and easy and highly accurate speed control operation with the index finger.

The fourth aspect is the medical hand set according to any one of the first to third aspects, in which the fingertip grip portion is gripped in a pen-holding style by the outer peripheral surface of the intermediate portion accommodating the electric motor. A palm-side grip portion to which the base end portion of the palm-side of the thumb and index finger of the operator is assigned is configured, and a rear portion for accommodating the battery as compared with the intermediate portion for accommodating the electric motor. Has a large outer peripheral length and extends rearward from the intermediate portion.

In the handset of this embodiment, more stable grip can be realized by using the intermediate portion having a larger outer peripheral length than the fingertip grip portion as the palm side grip portion. In addition, by making the rear part larger than the middle part, the storage space for batteries and boards is secured, and the handset slips off from the unintentional grip, especially the head of the medical attachment such as a shaft drill is almost vertically downward. It is possible to more effectively prevent the downward sliding due to the action of gravity when operating toward.

A fifth aspect is the medical handset according to any one of the first to fourth aspects, wherein the front portion in which the fingertip grip portion is formed has a cylindrical portion further extending toward the tip side. Is provided.

In the handset of this embodiment, by providing a tubular portion that extends further toward the tip side from the fingertip grip portion, the base end side of the medical attachment can be attached so as to be inserted into the tubular portion. Thereby, for example, as described in the embodiment described later, when the shaft drill, which is a kind of medical attachment, has a rotary shaft and an extrapolation sleeve (outer shaft), the extrapolation sleeve is fixed to the tubular portion. It is also easy to attach to. Further, it is possible to cover the base end side of the shaft drill with a cylindrical portion to reduce or avoid direct contact of the fingertip gripping the fingertip grip portion with the shaft drill. It is desirable that the tubular portion of this embodiment is formed with an outer peripheral length smaller than that of the front portion.

The sixth aspect is the medical handset according to any one of the first to fifth aspects, wherein the connecting portion to which the rear end of the shaft drill is connected is a cylinder made of synthetic resin in the rotary output shaft. It has a shape structure, and the input shaft of the medical attachment is inserted from the rear end and connected.

In the handset of this embodiment, a synthetic resin rotary output shaft is interposed between the tip of the rotary drive shaft of the electric motor and the input shaft of the medical attachment to reduce the absorption of vibration and shock in the drive connection portion. By improving the operability, the labor of the operator can be reduced and the heat generation of the member can be suppressed. In addition, the rotary output shaft made of synthetic resin realizes low friction at the connecting part with the medical attachment, allowing the relative movement of the rotary drive shaft of the electric motor and the medical attachment in the axial direction. At the same time, it is possible to stably transmit the rotational driving force.

A seventh aspect is a medical handset according to any one of the first to sixth aspects, wherein the medical attachment is inserted into a through hole in a lens barrel of a rigid endoscope and used. The electric motor is arranged so that the rotation drive shaft is located on an extension line of the rotation center axis of the shaft drill.

The shaft drill adopted as a medical attachment in the handset of this embodiment is relatively long, and it is said that stable treatment operation is difficult. However, by applying the handset according to the present invention to the shaft drill, cutting by a drill head is performed. It is possible to stabilize the procedure and facilitate the operation.

The eighth aspect is the medical handset according to the seventh aspect, wherein the shaft drill is extrapolated so as to be rotatable relative to a rotary shaft provided with a drill head at the tip and the rotary shaft. It is configured to include a sleeve-shaped outer shaft, and the base end of the rotary shaft is detachably connected to the rotary output shaft and is connected to the base end of the outer shaft. Is detachably fixed to the tip portion of the housing.

In the handset of this aspect, direct contact of the rotating shaft with the lens barrel is avoided under the insertion state of the rigid endoscope into the through hole in the lens barrel, and the lens barrel is protected. Further, it is also possible to improve the rotational stability of the rotary shaft by suppressing the shake of the rotary shaft in the long shaft drill with the outer shaft. Furthermore, by attaching the base end of the outer shaft to the tip of the housing, it is possible to prevent the base end of the rotating shaft from being exposed from the handset and prevent inadvertent contact of fingers, etc. with the rotating shaft. Become.

According to the present invention, it is possible to solve at least one of the problems inherent in a handset for driving a medical attachment operated by a rotational driving force around one axis such as a conventional shaft drill, for example. It is possible to provide a medical handset having a novel structure, which improves operability when a medical attachment such as a shaft drill is directed substantially vertically downward to perform a treatment operation.

A perspective view showing a handset as the first embodiment of the present invention in a state where a shaft drill, which is a kind of medical attachment, is attached. A perspective view showing the handset shown in FIG. 1 and a removable shaft drill. Top view showing the handset and removable shaft drill shown in FIG. Front view of half-cut fluoroscopy showing axial view from the tip side in the handset shown in FIG. Longitudinal section of the shaft drill shown in FIG. An exploded perspective view of the handset shown in FIG. A photograph for explaining an example of the usage state of the handset shown in FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1 to 4 show an example of a medical drill device 12 which is a medical hand device provided with a medical shaft drill 10 which is a kind of medical attachment. The medical drill device 12 has a structure in which a handpiece (handset) 14 as the first embodiment of the present invention is attached to a base end portion of a shaft drill 10. In the following description, as a general rule, the tip end side refers to the left side in FIG. 3 which is the drill head 16 side having a bit, and the base end side refers to the right side in FIG. 3 which is the handpiece 14 side. Further, as a general rule, the left-right direction means the left-right direction in FIG. 4 which is the width direction of the handpiece 14, and the up-down direction means the up-down direction in FIG. 4 which is the height direction of the handpiece 14. Further, the axial direction means, in principle, the central axial direction of the shaft drill 10 in the medical drill device 12.

As shown in FIGS. 2 to 3, the shaft drill 10 has a long (long and thin) shape as a whole, and is provided with a drill head 16 at the tip. The drill head 16 of the present embodiment has a substantially spherical shape, and cutting particles such as diamond are fixed to the outer peripheral surface and rotationally driven around the central axis of the shank 18 to cut bones and the like. Has been done. However, the specific shape, size, structure, etc. of the drill head 16 are not limited, and as disclosed in, for example, Japanese Patent Publication No. 2018-526175 and Japanese Patent No. 6129955, a fixed structure of cutting particles. Anything that can realize the desired medical cutting procedure, such as one equipped with a cutting edge instead of the above.

As shown in FIG. 5, the drill head 16 of the present embodiment has a rod-shaped shank 18 projecting toward the base end. The shank 18 of the present embodiment has a diameter smaller than the outer diameter of the drill head 16, and is capable of pulling backward in addition to pushing forward in the direction of the center axis of rotation. The drill head 16 and the shank 18 are integrally formed of a metal such as stainless steel for medical use or a titanium alloy.

The shank 18 is fixed to the tip of the elongated rod-shaped shaft body 20. The shaft body 20 of the present embodiment has a hollow cylindrical shape having a circular cross section and extends straight, and a good balance between high strength and weight is realized in terms of weight ratio. The shaft body 20 is made of a metal such as stainless steel for medical use or a titanium alloy, and it is desirable that a low friction coating layer is provided on the outer peripheral surface. The low-friction coating layer is a coating layer that enhances the slipperiness of the surface, and is known to be variously known, for example, fluororesin such as polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), silicon, and ceramic. Those can be adopted as appropriate. The outer diameter of the shaft body 20 is not particularly limited as long as it can be inserted into the outer shaft 36 described later, but is, for example, 2.75 mm.

It is desirable that the hollow portion in the shaft body 20 is filled with the filling 22. The filling 22 is not particularly limited, and may be a solid, a liquid, a gel-like body, or the like, and is partially or over the entire length of the hollow portion of the shaft body 20. The filling 22 of the present embodiment is a solid such as a synthetic resin, and is housed in the shaft main body 20. The filling 22 may be made of a single material as a whole, or may be formed of, for example, a tip portion and a base end portion made of different materials. In this case, the tip portion and the base end portion made of different materials may be independent of each other, and the entire filling 22 does not necessarily have to be continuous. Since the filling 22 is housed inside the hollow shaft body 20, the posture is stabilized by increasing the inertia during rotation, the shake during rotation of the shaft body 20 is suppressed, and the shaft is suppressed. The strength of the main body 20 can also be improved.

The padding 22 is not arranged at the tip of the shaft body 20, but the shank 18 is inserted and fixed to the tip of the hollow shaft body 20, and the rotating shaft 24 is formed by the shank 18 and the shaft body 20. It is configured. The rotating shaft 24 having a structure in which the shank 18 having a solid structure is inserted and fixed to the shaft body 20 having a hollow structure can efficiently secure the strength of the tip portion of the shaft body 20 close to the drill head 16 to which a particularly strong force is applied.

The fixed structure of the shank 18 and the shaft body 20 is not limited as long as it can withstand the axial force applied at the time of cutting and the rotational force around the shaft. , The shank 18 may be fixed by various means such as welding, bonding, pinning, caulking, and screwing in a state of being inserted into the shaft body 20, or by a fixing structure combining them. In addition, the shank 18 may have a hollow structure, and the tip end portion of the shaft main body 20 may be inserted and fixed from the base end side of the shank 18, or the shank 18 may be detachable from the shaft main body 20.

In the present embodiment, as shown in FIG. 5, a step portion 26 is formed at the tip portion of the rotating shaft 24 by the difference between the outer diameter of the shaft body 20 and the outer diameter of the shank 18. Further, the outer diameter of the drill head 16 is larger than the outer diameter of the shaft body 20.

An engaging member 28 is fixed to the base end of the rotating shaft 24. The engaging member 28 has a bottomed cylindrical shape, and the base end portion of the shaft body 20 is fixed in the inserted state. It is desirable that the engaging member 28 is made of a material capable of achieving low friction on the surface and low heat transfer coefficient.

The engaging member 28 of the present embodiment is made of synthetic resin, and is formed of, for example, PEEK having a small surface friction coefficient, a small heat transfer coefficient, and excellent heat resistance. The engaging member 28 includes an engaging ridge 30 that projects outward and extends in the axial direction. By forming unevenness in the circumferential direction, the engaging ridge 30 can regulate or prevent relative rotation around the central axis with respect to the rotation output shaft 52 in the handpiece 14, which will be described later. It suffices as long as it can realize a combined state, and in the present embodiment, the engaging member 28 is separated from each other in the circumferential direction so as to extend continuously and linearly in the axial direction at a plurality of locations (for example, four locations). Although it is provided, the number of formations, arrangement, and the like are not particularly limited as long as they are compatible with the rotary output shaft 52. The engaging ridge 30 of the present embodiment extends in the axial direction with a substantially semicircular cross section, but may have another cross-sectional shape such as a substantially rectangular cross section.

The engaging member 28 has a polygonal cross-sectional outer peripheral shape such as a hexagon corresponding to the rotation output shaft 52 of the handpiece 14, so that the engaging ridge 30 does not need to be specially provided. .. Further, in order to improve the relative fixing strength in the circumferential direction and the axial direction with respect to the rotating shaft 24, the engaging member 28 is provided with, for example, an uneven locking structure on the fitting surface, a connecting shaft structure penetrating in the radial direction, and the like. It is also possible to adopt it, or a resin filling 22 protruding toward the base end side of the rotary shaft 24 may be welded to the engaging member 28 or the like.

A gap ring 32 is extrapolated to the rotating shaft 24. The gap ring 32 is made of synthetic resin like the engaging member 28, and is formed of, for example, PEEK. The gap ring 32 is extrapolated so as to be rotatable relative to the rotating shaft 24. The gap ring 32 is formed with a lightening recess 34 that opens on the outer peripheral surface, and the heat dissipation performance is improved and the weight is reduced by increasing the surface area. The gap ring 32 is extrapolated to the rotating shaft 24 on the distal end side of the engaging member 28. The outer peripheral surface of the gap ring 32 has a larger diameter than the engaging member 28, and the outer peripheral surface is located on the outer peripheral side of the tip of the engaging ridge 30 of the engaging member 28.

The outer shaft 36 is extrapolated to the rotating shaft 24. The outer shaft 36 has a sleeve shape having an inner diameter slightly larger than the outer diameter of the shaft main body 20. The outer shaft 36 is made of a metal such as stainless steel for medical use or a titanium alloy. The outer shaft 36 is extrapolated to the shaft body 20, and the rotating shaft 24 is rotatable within the outer shaft 36. It is desirable that the inner peripheral surface and the outer peripheral surface of the outer shaft 36 are provided with a low friction coating layer as in the outer peripheral surface of the shaft main body 20. The inner diameter of the outer shaft 36 is not particularly limited as long as the rotating shaft 24 can be inserted, but is, for example, 2.8 mm.

The connector 38 is fixedly attached to the base end portion of the outer shaft 36. The connector 38 is made of a synthetic resin material such as polycarbonate. The connector 38 has a hollow cylindrical shape as a whole, and the outer shaft 36 is fixed to the inner peripheral surface. The connector 38 is provided with an operation piece 40 projecting from the outer peripheral surface at the tip portion thereof. In the present embodiment, the operation piece 40 has a substantially elliptical plate shape and may have a disk shape. However, in order to prevent the shaft drill 10 from rolling, the outer peripheral surface shape of the operation piece 40 is other than circular. It is preferable that the outer diameter is different in the circumferential direction, such as an ellipse or a polygon.

Further, the connector 38 is provided with a connecting protrusion 42 that partially protrudes on the outer periphery of the base end portion. The connecting protrusion 42 is a ridge extending in a substantially U-shaped or U-shaped shape with the tip side open in the top view, and is located on both sides of a straight line portion that faces each other in the circumferential direction and extends in the axial direction of the shaft. Is formed with a pair of locking

portions

44, 44 protruding outward from the left and right at an intermediate portion in the axial direction of the shaft. Further, a flange-shaped protrusion 43 projecting on the outer peripheral surface of the connector 38 is formed on the tip end side of the connecting protrusion 42.

The base end portion of the connector 38 is substantially the same as the base end portion of the outer shaft 36, but protrudes rearward in the axial direction with a predetermined length. Further, the base end side of the rotary shaft 24 inserted through the outer shaft 36 in a penetrating state protrudes from the connector 38. The gap ring 32 extrapolated to the rotary shaft 24 is arranged between the connector 38 provided at the base end portion of the outer shaft 36 and the engaging member 28 provided at the base end portion of the rotary shaft 24 in the axial direction. Has been done. The gap ring 32 has a larger diameter than the outer shaft 36, and cannot be inserted into the outer shaft 36. The outer diameter of the gap ring 32 is larger than the opening diameter on the base end side of the connector 38.

The rotary shaft 24 can move relative to the outer shaft 36 by a predetermined distance in the axial direction, and the engaging member 28 passes through the gap ring 32 at the moving end of the rotary shaft 24 with respect to the outer shaft 36 toward the tip end side. It is defined by abutting on the connector 38. Further, the exit of the rotary shaft 24 to the rear end side with respect to the outer shaft 36 is defined by the contact of the drill head 16 having an outer diameter larger than the inner diameter of the outer shaft 36 with the tip opening of the outer shaft 36. .. When the drill head 16 has a small diameter, a protrusion for retaining may be provided on the tip of the shank 18 or the shaft body 20 protruding from the outer shaft 36, or a ring member may be externally fitted and fixed.

The handpiece 14 to which such a shaft drill 10 is detachably attached and exerts a rotational driving force around one axis on the shaft main body 20 is a device that the practitioner grips and operates by hand. As shown in a disassembled manner in FIG. 6, the handpiece 14 of the present embodiment includes an electric motor 46 that generates a rotational driving force inside a hollow housing 45, a battery pack that supplies electric power to the electric motor 46, and the like. A power supply device 48, which is a battery, and a control board 50 that controls power supply from the power supply device 48 to the electric motor 46 are built-in. That is, the handpiece 14 has a built-in energy source and a drive device, and does not require a cable or the like for connecting to an external energy source.

The housing 45 is composed of a pair of left and right housing divided

bodies

45a and 45b having a substantially symmetrical shape. Each of the

housing divisions

45a and 45b has a boat-shaped bottomed shape having a substantially constant thickness as a whole, and the peripheral walls are abutted against each other so that the end edges of the openings are overlapped with each other. By mutually positioning and fixing with fixing bolts or the like, the housing 45 is formed as a housing having a housing interior that is substantially closed to the external space.

The housing 45 extends long in an axial direction corresponding to the rotation center axis Z of the shaft drill 10 to be mounted (the center axis of the engaging member 28 which is the input axis of the shaft drill 10) and has different outer peripheral lengths. Compared to the intermediate portion A in the axial direction, the front portion B located on the distal end side in the axial direction has a smaller outer peripheral length, and the rear portion C located on the proximal end side in the axial direction has a larger outer peripheral length. In particular, in the present embodiment, the intermediate portion A, the front portion B, and the rear portion C each have a hollow cylindrical portion extending with a substantially constant outer peripheral shape, and the intermediate portion A, the front portion B, and the rear portion C are provided. Between each axial direction, an inclined surface region is provided in which the outer peripheral length gradually changes in the axial direction and smoothly connects the respective portions A, B, and C.

Further, in the present embodiment, in any of the intermediate portion A, the front portion B, and the rear portion C, each corner portion has a substantially rectangular outer peripheral cross-sectional shape with roundness, and the pair of short side portions are upper and lower. In addition to being located at, the shape is such that a pair of long sides are located on the left and right.

In particular, the intermediate portion A in the axial direction has an outer peripheral surface shape close to a substantially square or circular shape, and is located inside the intermediate portion A to accommodate the electric motor 46 and is fixedly inside the housing 45. It is positioned. Then, the rotation drive shaft 51 of the electric motor 46 extends so as to coincide with the extension line of the rotation center axis Z of the shaft drill 10 to be mounted.

Further, a rotary output shaft 52 to which an engaging member 28 of the rotary shaft 24 constituting the shaft drill 10 is connected is attached to the tip of the rotary drive shaft 51 so as to be relatively non-rotatable. The rotary output shaft 52 extends from the intermediate portion A toward the tip end side in the axial direction, and is arranged in the front portion B of the housing 45.

The front portion B of the housing 45 is one size smaller than the intermediate portion A, and as shown in FIG. 4, the height dimension Y is slightly larger than the width dimension X, and each corner portion is formed. Is rounded and has a substantially rectangular outer peripheral shape. In the present embodiment, the width dimension X of the front portion B is smaller than the outer diameter dimension φD of the motor main body portion of the electric motor 46 housed in the intermediate portion A.

A fingertip grip portion for gripping the housing 45 by the outer peripheral surface of the front portion B extending toward the tip end side in the axial direction with such a small outer circumference, and holding the entire shaft drill 10 by hand during treatment such as human bone cutting. Is configured. It is desirable that the outer peripheral surface of the front portion B, which is the fingertip gripping portion, has an outer peripheral length set within the range of 100 mm to 150 mm. As a result, as illustrated in FIG. 7, the operator grips the housing 45 with a pen holding style with a fingertip while the central axis of the housing 45 is substantially vertical and the tip of the housing 45 is oriented substantially vertically downward. A size that is particularly suitable for the above can be realized.

However, the outer peripheral lengths of the intermediate portion A, the front portion B, and the rear portion C are appropriately set and are not limited according to the intended use of the handpiece 14 and the mounting attachment. Preferably, the outer peripheral length of the intermediate portion A is set within the range of 100 mm to 150 mm. Considering general usage conditions, it is desirable that the outer peripheral length of the front portion B is smaller than that of the intermediate portion A, but for example, it is possible to make the outer peripheral length of the intermediate portion A and the front portion B equal. By making the outer peripheral lengths of both substantially equal, it is possible to facilitate holding in the pen holding style not only in the front portion B but also in the intermediate portion A depending on the situation. In short, by setting at least the outer peripheral length of the intermediate portion A ≥ the outer peripheral length of the front portion B, the grip of the handpiece 14 in the pen-holding style is good.

Further, the rotary output shaft 52 arranged in the front end portion B in a housed state is provided with a connection hole that opens on the tip surface, and constitutes the proximal end side of the rotary shaft 24 with respect to the connection hole. The engaging member 28 is inserted from the rear end so that it cannot rotate relative to each other in the circumferential direction and is detachably connected in an engaged state. The rotary drive shaft 51 of the electric motor 46 is generally a solid rod made of metal, whereas the rotary output shaft 52 is made of heat transfer or synthetic resin having a smaller coefficient of friction than metal. desirable. By adopting a rotary output shaft made of synthetic resin, it is possible to increase the degree of freedom in design such as the degree of freedom in selecting the material and the degree of freedom in setting the member thickness, while ensuring good mass productivity. It is easy to flexibly respond to the required characteristics, and it is easy to adjust the weight balance of the handpiece 14 while considering operability. Further, it is desirable that the rotary output shaft 52 is rotatably supported by the housing 45 at its tip portion or the like via a bearing 53.

Further, a speed control switch 58 for adjusting the rotation speed of the electric motor 46 is provided on the front portion B of the housing 45. It is desirable that the speed governor switch 58 is located on the surface of the short side portion narrowed in the front portion B, and is provided so that the speed governor can be operated in the axial direction of the housing 45. As a result, the rotation speed of the electric motor 46 can be further adjusted and adjusted by the speed governor switch 58 (while stably securing the gripping force of the housing 45 by other fingers) with only the finger, for example, the index finger that grips the front portion B. It will be possible to do it easily. The speed control switch 58 is generally designed to convert the amount of movement (operation amount) of the operation portion by the fingers into an electric signal and transmit it to the control board 50 described later, and the conversion of the movement amount into an electric signal. The mechanism may be disposed in the outer peripheral space of the rotary output shaft 52 in the destination portion B, for example, as shown in FIG.

Further, the housing 45 of the present embodiment is provided with a small-diameter cylindrical connecting cylinder portion 60 projecting forward from the tip end portion of one housing split body 45a, and the connecting cylinder portion 60 is provided with a rotary output shaft 52. It is located forward in the axial direction of the housing 45 and extends on the central axis of the housing 45. When the shaft drill 10 is attached, the base end portion of the connector 38 of the outer shaft 36 is inserted into the connection cylinder portion 60 so as to be locked and connected.

The connection cylinder portion 60 is provided with a notch-shaped connecting recess 62 at the upper portion, and the connecting recess 62 is open toward the front in the top view shown in FIG. 3, and is connected to the connector 38. The protrusion 42 can be inserted in the axial direction. Further, on the facing inner surfaces on both the left and right sides facing each other in the circumferential direction in the connecting recess 62, locking recesses 64, 64 corresponding to the locking

portions

44, 44 of the connecting protrusion 42 are formed. Then, the connecting protrusion 42 of the connector 38 is inserted into the connecting recess 62 of the handpiece 14, and the locking

portions

44, 44 of the connecting protrusion 42 are engaged with the locking recesses 64, 64 of the connecting recess 62. This limits the axial disconnection of the connector 38 from the connection cylinder portion 60. As a result, the shaft drill 10 is maintained in a mounted state on the handpiece 14 (housing 45).

The shaft drill 10 mounted in this way is an electric motor due to the holding action of the rotating shaft 24 (engaging member 28) by the rotating output shaft 52 and the holding action of the outer shaft 36 (connector 38) by the connecting cylinder portion 60. The rotation center axis of the 46 and the rotation center axis of the shaft drill 10 are stably maintained in a aligned state. Then, the rotational driving force of the electric motor 46 is applied to the rotary shaft 24 via the rotary output shaft 52, so that the rotary shaft 24 rotates around the central axis in the outer shaft 36 fixedly attached to the handpiece 14. The drill head 16 is rotationally driven to rotate. When removing the shaft drill 10 from the handpiece 14, for example, the operation piece 40 of the connector 38 can be manually pulled out from the handpiece 14 in the axial direction.

The structure of connecting the shaft drill 10 to the handpiece 14 is not limited. For example, unevenness for positioning can be appropriately provided between the inner peripheral surface of the connecting cylinder 60 and the outer peripheral surface of the outer shaft 36 (connector 38), and the rotating shaft 24 can be rotated with respect to the handpiece 14. It is also possible to adopt a bearing member to support. Further, a known chuck structure may be adopted in the mounting portion of the rotating shaft 24 to the rotary output shaft 52 and the mounting portion of the outer shaft 36 to the connecting cylinder portion 60.

As described above, since the shaft drill 10 can be attached to and detached from the handpiece 14 of the present embodiment, the size can be reduced and various shaft drills having different lengths and bits depending on the treatment can be obtained. Can be appropriately selected and attached, and various medical attachments other than the shaft drill can be attached as needed, as will be described later. Further, since the shaft drill 10 and the handpiece 14 can be separated from each other, for example, the shaft drill 10 can be used once and the handpiece 14 can be used a plurality of times. It can be kept clean and the cost can be reduced by using the expensive handpiece 14 multiple times.

On the other hand, the rear portion C of the housing 45 is slightly larger than the intermediate portion A, and as shown in FIG. 4, the intermediate portion A in both the width dimension X and the height dimension Y. It has a substantially rectangular outer peripheral cross-sectional shape with a larger size.

As shown in FIG. 6, a power supply device 48 composed of a battery pack is housed and positioned in the rear portion C where the internal space is increased in this way. Further, in the present embodiment, the control board 50 that controls the power supply from the power supply device 48 to the electric motor 46 is located between the electric motor 46 and the power supply device 48 and is arranged so as to spread in the direction perpendicular to the axis. The power supply 48 is located close to the rear end in the housing 45. As shown in FIG. 6, in the present embodiment, by arranging a plurality of (two) battery packs on the extension line of the rotation center axis Z, the outer peripheral length of the rear portion C becomes larger than necessary. While avoiding this, the storage capacity of the power supply device 48 is secured.

Further, in the present embodiment, the upper part of the rear portion C (upper part in FIG. 4) protrudes in a substantially chevron shape, and as shown in FIG. 6, the main switch 56 is located in the chevron-protruding portion. , The operation buttons are arranged in a state of being exposed on the surface of the housing 45. The main switch 56 is an operation unit that controls the power supply to the electric motor 46 housed in the intermediate portion A to turn on / off the rotation of the drill head 16.

By arranging the main switch 56 at a large distance in the axial direction of the housing 45 from the tip portion B constituting the fingertip grip portion, the finger gripping the fingertip grip portion carelessly touches the main switch 56 and the drill operation is stopped. Or the risk of being started can be reduced.

Further, by arranging the electric motor 46, the power supply device 48, and the control board 50 in the housing 45 at a position axially rearward from the front portion B constituting the fingertip grip portion, their electric actuation mechanisms generate heat. However, the risk of discomfort caused by the gripping fingers can be reduced. Further, by providing an intermediate portion A having a large outer peripheral length behind the front portion B constituting the fingertip grip portion in the axial direction, as shown in FIG. 7, when the front portion B is gripped in a pen-holding style, the tip portion B is gripped. By applying the palm region corresponding to the base portion between the thumb and the one-point finger to the outer peripheral surface of the intermediate portion A, the holding stability of the housing 45 in the pen-holding style can be improved. Moreover, in the gripping state in the pen-holding style as shown in FIG. 7, an intermediate portion A having a larger outer peripheral length is located above the tip portion B constituting the fingertip grip portion, and a larger outer portion is located. Since the rear portion C of the peripheral length is located further above the intermediate portion A, the risk that the gripping position with the fingertips shifts upward due to the weight of the electric motor 46 or the power supply device 48 can be reduced. ..

Further, the front portion B constituting the fingertip grip portion connects the rotary output shaft 52 to the rotary drive shaft 51 of the electric motor 46, so that the tip end side of the housing 45 is moved forward from the intermediate portion A in which the electric motor 46 is arranged. Toward, it was extended with an outer peripheral length smaller than that of the intermediate portion A (particularly, in the present embodiment, with a width dimension X smaller than the outer diameter of the electric motor 46). As a result, the outer peripheral length is reduced, and a shape and size suitable for gripping in a pen-holding style can be realized without being limited to an contained object such as an electric motor 46. In particular, in the present embodiment, since the front portion B has a rounded rectangular outer peripheral cross-sectional shape, it is easier to grip in the pen-holding style and can be realized while being conscious of the direction. There is. In addition, since the speed control switch 58 that can be operated in the axial direction is arranged in the substantially flat area on the short side side that is the upper surface of the front portion B, it is possible to hold the speed with a fingertip by the pen holding style. It may be easier to adjust the motor rotation speed with a pointing finger.

Since the tip portion B of the housing 45 can be gripped in a pen-holding style, when the drill head 16 of the shaft drill 10 is operated substantially vertically downward, for example, in endoscopic spinal surgery. The housing 45 can be easily gripped, the labor of the practitioner can be reduced, and the stability and accuracy of operations such as cutting can be improved. In particular, the housing 45 is gripped in a pen-holding style, and the centers of gravity of the heavy electric motor 46 and the power supply device 48 (M1 and M2 in FIG. 2) are substantially extended on the rotation center axis Z of the shaft drill 10. Combined with the fact that it is placed in, when the shaft drill 10 is operated substantially vertically downward, for example, in endoscopic spinal surgery, the weight of the handpiece 14 itself is the center of rotation of the shaft drill 10. It can be used as a pushing force in the axis Z direction, and the labor of the practitioner can be further reduced and the operability can be improved. In addition, with respect to the long shaft drill 10 mounted on the handpiece 14, a fingertip grip portion is provided on the tip end side (front portion B) of the handpiece 14 which is the mounting position of the shaft drill 10. It can support a position as close as possible to the shaft drill 10. That is, since the distance between the drill head 16 to which the cutting reaction force is input and the support point (O in FIG. 2) of the handpiece 14 can be shortened as much as possible, the shaft drill 10 itself swings due to the cutting reaction force. It is also possible to efficiently apply a force effective for suppressing tilting or tilting at the fingertip gripping portion.

Further, as described in FIG. 2, the support center O by the fingers gripping the outer peripheral surface of the front portion B is substantially on an extension line of the rotation center axis Z extending in the axial direction through substantially the center of the housing 45. Will be located. Then, on the substantially extension line of the rotation center axis Z, the center of gravity M1 of the electric motor 46 is located rearward from the support center O at the substantially center in the axial direction of the intermediate portion A. Further, the center of gravity M2 of the power supply device 48, which is farther rearward from the support center O and has a mass larger than that of the electric motor 46, is located on a substantially extension of the rotation center axis Z at substantially the center of the rear portion C in the axial direction. ..

As described above, the centers of gravity M1 and M2 of the heavy electric motor 46 and the power supply device 48 are set relatively large rearward on the central axis from the support center O of the handpiece 14 by the fingers. A large moment of inertia in the tilting direction around the support center O is secured. Therefore, when performing human bone cutting with the shaft drill 10 mounted on the tip side using the handpiece 14, tilting is suppressed and stable cutting is performed even when a resistance reaction force is applied from the drill head 16. The operation becomes feasible.

Further, since the rotation drive shaft 51 of the electric motor 46 and the rotation center axis Z of the shaft drill 10 (rotation shaft 24) are arranged on the same axis, the rotation drive reaction force of the shaft drill 10 by the electric motor 46 is applied. The resulting blur is prevented. Moreover, the rotation direction of the handpiece 14 is obtained by substantially positioning the centers of gravity M1 and M2 of the electric motor 46 and the power supply device 48, which are particularly heavy parts of the handpiece 14, on the rotation center axis Z of the shaft drill 10. By moving the inertial center axis of the shaft drill 10 (rotating shaft 24) closer to the extension line of the rotation center axis Z of the shaft drill 10 (rotating shaft 24), shaft shake due to the rotational drive reaction force of the shaft drill 10 can be suppressed and rotational stability can be improved. ..

Incidentally, the medical drill instrument 12 of the present embodiment having the structure as described above has a substantially vertical direction (slightly inclined state) as shown in FIG. 7 when cutting a bone in, for example, an endoscopic operation. It is used by being inserted into a rigid endoscope 66 in which the tip side facing downward is inserted into the human body while being supported by (including). As virtually shown in FIG. 3, the rigid endoscope 66 includes a rigid lens barrel 68, and a shaft drill 10 is inserted through a through hole 70 penetrating the lens barrel 68. The drill head 16 of the shaft drill 10 may be positioned so as to project toward the tip end side from the lens barrel 68. The rigid endoscope 66 is provided with a camera, a light, or the like (not shown) at the tip portion thereof, and the drill head 16 protruding from the lens barrel 68 to the tip can be visually recognized under the endoscope. The base end portion of the shaft drill 10 projects toward the base end side of the lens barrel 68 so that the handpiece 14 is located closer to the base end side than the lens barrel 68. It is desirable that the outer peripheral surface of the outer shaft 36 is in contact with or slightly separated from the inner peripheral surface of the through hole 70 of the rigid endoscope 66.

Since the outer shaft 36 is made of metal, it has high strength and can sufficiently obtain pushability when it is inserted into the through hole 70 of the rigid endoscope 66. It is desirable that a low-friction coating layer be provided on the outer peripheral surface of the outer shaft 36, and when the shaft drill 10 is inserted into the through hole 70 of the rigid endoscope 66, frictional resistance and catching are suppressed and it is easy. Can be inserted into. Further, when liquids such as blood and physiological saline, and cut bone fragments (cutting debris) are supplied and discharged through the through hole 70, the inner peripheral surface of the through hole 70 and the outer peripheral surface of the outer shaft 36 are also supplied and discharged. The resistance when moving between and is reduced, and the field of view under the endoscope is secured by discharging the physiological saline solution, and the efficient discharge of cutting chips by suction is realized.

Further, as shown in FIG. 7, when the practitioner grips and uses the handpiece 14 and the lens barrel 68, the outer shaft 36 is integrally connected to the handpiece 14, so that the practitioner intentionally It does not rotate with respect to the rigid endoscope 66 except when it is rotated to. The rotary shaft 24 inserted through the outer shaft 36 is rotated around the central axis by the driving force of the electric motor 46 in the outer shaft 36 inserted through the through hole 70 of the lens barrel 68. In a state where the shaft drill 10 is inserted through the through hole 70, the outer shaft 36 is interposed between the rotating shaft 24 and the rigid endoscope 66, and contact between the rotating shaft 24 and the rigid endoscope 66 is avoided. .. In addition, in FIG. 3, the cross section of the rigid endoscope 66 passing through the through hole 70 is shown.

The medical drill device 12 can scrape the bone by bringing the rotating drill head 16 into contact with the bone to be cut under the endoscope. At least one of the outer peripheral surface of the rotating shaft 24 continuous with the drill head 16 and the inner peripheral surface of the outer shaft 36 inserted into the through hole 70 of the rigid endoscope 66 has a low friction coating layer. Therefore, the rotary shaft 24 can be efficiently rotated in the outer shaft 36, and heat generation due to friction is also reduced. Since the rotary shaft 24 is made of metal, it has high strength, and since it is supported by the metal outer shaft 36, the drill head 16 can be brought into contact with the bone with sufficient force. At the same time, blurring and damage due to bending of the rotating shaft 24 due to the reaction force when the drill head 16 comes into contact with the bone are prevented.

Further, since the contact of the rotating shaft 24 with the rigid endoscope 66 is avoided, damage and heating of the rigid endoscope 66 due to the contact with the rotating shaft 24 are prevented. Further, by adjusting the thickness dimension and the diameter dimension of the outer shaft 36 according to the difference between the outer diameter dimension of the rotary shaft 24 and the inner dimension of the through hole 70 of the rigid endoscope 66, the rotary shaft 24 can be formed. It can be appropriately guided by the outer shaft 36, and the blurring of the rotating shaft 24 during rotation can be suppressed more efficiently.

Furthermore, the rotary shaft 24 is movable relative to the rotary output shaft 52 and the outer shaft 36 of the handpiece 14 by a predetermined distance in the axial direction, but when the rotary shaft 24 is moved to the protruding tip side. , Heating or damage due to contact between the engaging member 28 of the rotating shaft 24 and the outer shaft 36 (connector 38) can be reduced or avoided by the gap ring 32. That is, since the gap ring 32 is capable of relative rotation with respect to both the rotary shaft 24 and the outer shaft 36, the gap ring 32 may rotate with the rotational operation of the rotary shaft 24, but the gap ring 32 may rotate. The rotation speed of is lower than the rotation speed of the rotary shaft 24. Therefore, frictional heat and resistance can be reduced as compared with the case where the engaging member 28 rotating at high speed is in direct contact with the outer shaft 36. In particular, in the present embodiment, since the resin connector 38 is provided on the base end side of the outer shaft 36 so that the gap ring 32 comes into contact with the connector 38, the frictional heat due to the contact of the gap ring 32 comes into contact with the connector 38. Can be suppressed more effectively.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited by the specific description thereof. For example, the specific structure of the shaft drill 10 is not limited, and various conventionally known shaft drills 10 can be mounted. Then, depending on the structure of the mounting portion of the shaft drill 10, the structure of the rotary output shaft 52, the connecting cylinder portion 60, and the like in the handpiece 14 can be appropriately changed.

Further, the medical attachment attached to the medical handset according to the present invention is not limited to the above-mentioned shaft drill, but is connected to the rotary output shaft of the medical attachment and is uniaxially rotated from the rotary output shaft. Various medical attachments that are activated by exerting a rotational driving force can be applied. For example, an attachment equipped with a rotary input shaft that is rotationally driven around one axis and a cutting blade such as a saw or a cutter that is reciprocated via a motion conversion mechanism that converts the rotary motion of the rotary input shaft into reciprocating motion or the like. Can also be attached to the medical handset according to the present invention.

Further, the electric motor 46, the power supply device 48, the electric control system by the control board 50, etc. adopted in the handpiece 14 are not limited. The position of the main switch 56 is not limited, and for example, it may be provided on the rear end surface of the handpiece 14, or a toggle switch other than the pressing switch may be adopted. Further, the specific structure, shape, arrangement position, etc. of the speed governor 58 are not limited, and for example, a rotary type or dial type operation unit that continuously or stepwise controls the speed is adopted. You can also do things. However, the provision of the speed control switch 58 itself is not essential in the present invention. For example, the electric motor 46 can be driven with a constant power supply, or power can be supplied to the electric motor 46 (torque) according to the rotational reaction force (cutting resistance). It is also possible to adopt a control circuit or the like that adjusts).

10 Shaft drill (medical attachment)
12 Medical drill equipment 14 Handpiece (handset)
16 Drill head 18 Shank 20 Shaft body 22 Filling 24 Rotating shaft 26 Step 28 Engagement member 30 Engagement ridge 32 Gap ring 34 Lightening recess 36 Outer shaft 38 Connector 40 Operation piece 42 Connecting protrusion 43 Flange-shaped protrusion 44 Locking part 45 Housing 46 Electric motor 48 Power supply (battery)
50 Control board 51 Rotation drive shaft 52 Rotation output shaft 53 Bearing 54 Connection recess 56 Main switch 58 Governor switch 60 Connection cylinder (cylindrical part)
62 Connecting recess 64 Locking recess 66 Rigid endoscope 68 Lens barrel 70 Through hole A Intermediate part B Tip part (fingertip grip part)
C rear part Z rotation center axis

Claims

A medical handset to which a medical attachment is attached and exerts a rotational driving force around one axis on the medical attachment.
Equipped with an electric motor as a drive source,
It is arranged coaxially with the rotary drive shaft of the electric motor so as to extend toward the front side, the rotary drive shaft is connected to the rear end, and the input shaft of the medical attachment is connected to the tip. A rotary output shaft is provided.
A battery is arranged on the rear side coaxially with the rotary drive shaft of the electric motor.
It is equipped with a housing containing the electric motor, the rotary output shaft, and the battery, and
In the housing, the front portion accommodating the rotary output shaft extends from the intermediate portion toward the tip side with the same or smaller outer peripheral length as compared with the intermediate portion accommodating the electric motor.
A medical handset in which a fingertip gripping portion that is gripped by an operator in a pen-holding style with a fingertip is configured by the outer peripheral surface of the tip portion.
The medical handset according to claim 1, wherein a speed control switch for adjusting the rotation speed of the electric motor is provided on the outer peripheral surface of the fingertip grip portion.
The outer peripheral surface constituting the fingertip grip portion in the front portion has a rounded rectangular outer peripheral cross-sectional shape, and the speed control switch is arranged so as to operate in the axial direction on the short side. The medical handset according to claim 2.
The outer peripheral surface of the intermediate portion accommodating the electric motor constitutes a palm-side grip portion to which the base end portion of the palm side of the thumb and index finger of the operator who grips the fingertip grip portion in a pen-holding style is applied. With
The invention according to any one of claims 1 to 3, wherein the rear portion accommodating the battery extends rearward from the intermediate portion with a large outer peripheral length as compared with the intermediate portion accommodating the electric motor. The listed medical handset.
The medical handset according to any one of claims 1 to 4, wherein the tip portion including the fingertip grip portion is further provided with a tubular portion extending toward the tip side.
In the rotary output shaft, the connecting portion to which the input shaft of the medical attachment is connected has a cylindrical structure made of synthetic resin, and the input shaft of the medical attachment is inserted and connected from the rear end. The medical handset according to any one of claims 1 to 5.
The medical attachment is a medical shaft drill used by being inserted into a through hole in a barrel of a rigid endoscope, and the rotation drive shaft is located on an extension of the rotation center axis of the shaft drill. The medical hand set according to any one of claims 1 to 6, wherein the electric motor is arranged so as to be used.
The shaft drill includes a rotary shaft provided with a drill head at the tip and a sleeve-shaped outer shaft extrapolated so as to be extrapolated relative to the rotary shaft.
The base end of the rotary shaft is detachably connected to the rotary output shaft, and is also connected to the rotary output shaft.
The medical handset according to claim 7, wherein the base end of the outer shaft is detachably fixed to the tip end portion of the housing.