DE202018106457U1 - Leaf spring for resetting a surgical punching instrument and surgical punching instrument - Google Patents

Abstract

A leaf spring (22, 22 ', 22a, 22b) for resetting a surgical punch (10) after actuation, comprising: a mounting portion (28) for securing the leaf spring to a handle (16) integral with a guide shaft (12) of the surgical punch ) of the surgical punching instrument or to a handle (20) of the surgical punch, movable relative to the handle, the attachment portion having an opening (34) for passing a fastener to secure the leaf spring to the handle or to the operating lever; a coupling portion (30 ) for flexibly connecting the leaf spring to a second leaf spring; anda bendable spring portion (32) between the attachment portion and the spring force applying coupling portion so that the operation lever and handle for returning the surgical punch are guided away from each other, wherein a width (b) of the leaf spring in its attachment portion in the region of the opening is at least one diameter ( d) the opening is greater than a width (f) of the leaf spring in its spring portion.

Description

The present invention relates to a leaf spring for resetting a surgical punching instrument after actuation and a surgical punching instrument, in particular a bone punch, for removing a tissue or bone sample.

Surgical punches are used in medical applications to separate tissue or bone samples so that they can be examined. Such instruments usually have a guide shaft and a punch slide which is displaceably mounted on this guide shaft, wherein cutting surfaces which can be pressed against one another are attached to the guide shaft and the punch slide, by means of which the tissue or bone sample can be separated. The sample may then be removed from the human body after removal of the surgical punch from the punching instrument.

In order to operate the surgical punching instrument, usually a handle and a relative to this handle movable operating lever is used. By actuating the actuating lever of the punch slide is moved relative to the guide shaft, so that the sample to be removed is cut out. In order to return the surgical punching instrument after actuation back to the starting position, it is advantageous if a spring for exerting a restoring spring force is arranged between the actuating lever and the handle.

In the DE 43 16 768 A1 an instrument for surgical purposes is disclosed. In the instrument two relatively movable workpieces are provided with two relatively pivotable gripping branches. Of the gripping industries is one with the one and the other with the other working part in such connection that when closing or opening the handle branches, the two working parts are moved against each other. To reset the handle branches after actuation, a spring is arranged between the handle branches.

A challenge in designing the resetting mechanism for surgical punches is that the instruments are exposed to relatively high forces when used. A robust construction is therefore required. On the one hand, the force required for the return must be large enough to effect the return movement. On the other hand, the force should not be too large, otherwise comfortable use by a physician or trained medical personnel is not possible. In that regard, the restoring force are set relatively narrow limits.

Often one or two leaf springs are used to exert the restoring force between the operating lever and the handle. Such leaf springs have the advantage that the force exerted based on the dimensions (width and thickness) can be easily and precisely specified. Especially with smaller or thinner leaf springs, however, it can also lead to mechanical defects, such as fatigue fractures in particular.

Based on this, the present invention has the problem of providing a leaf spring for resetting a surgical punching instrument, which on the one hand robust and on the other hand precisely dimensioned, so that the restoring force to be exercised can be determined.

• - einem Befestigungsabschnitt zum Befestigen der Blattfeder an einem fest mit einem Führungsschaft des chirurgischen Stanzinstruments verbundenen Handgriff des chirurgischen Stanzinstruments oder an einem gegenüber dem Handgriff beweglichen Betätigungshebel des chirurgischen Stanzinstruments, wobei der Befestigungsabschnitt eine Öffnung zum Durchführen eines Befestigungsmittels aufweist, um die Blattfeder an dem Handgriff oder an dem Betätigungshebel zu befestigen;
• - einem Kopplungsabschnitt zum flexiblen Verbinden der Blattfeder mit einer zweiten Blattfeder; und
• - einem biegbaren Federabschnitt zwischen dem Befestigungsabschnitt und dem Kopplungsabschnitt zum Ausüben einer Federkraft, sodass Betätigungshebel und Handgriff zum Rückstellen des chirurgischen Stanzinstruments voneinander weggeführt werden,
• - wobei eine Breite der Blattfeder in ihrem Befestigungsabschnitt im Bereich der Öffnung zumindest um einen Durchmesser der Öffnung größer ist als eine Breite der Blattfeder in ihrem Federabschnitt.

To achieve this object, in a first aspect, the present invention relates to a leaf spring for resetting a surgical punching instrument after actuation, comprising:

• a fixing portion for fixing the leaf spring to a handle of the surgical punch fixedly connected to a guide shaft of the surgical punch, or to a handle of the surgical punch that is movable relative to the handle, the fixing portion having an opening for passing a fastener to the leaf spring on the handle or to be attached to the operating lever;
• a coupling portion for flexibly connecting the leaf spring to a second leaf spring; and
• a bendable spring portion between the attachment portion and the coupling portion for applying a spring force, so that the operation lever and the handle for returning the surgical punching instrument are led away from each other,
• - Wherein a width of the leaf spring in its attachment portion in the region of the opening at least by a diameter of the opening is greater than a width of the leaf spring in its spring portion.

• - einem Führungsschaft und einem daran verschiebbar gelagerten Stanzschieber;
• - einem fest mit dem Führungsschaft verbundenen Handgriff zum Handhaben des chirurgischen Stanzinstruments;
• - einem gegenüber dem Handgriff beweglichen Betätigungshebel zum Verschieben des Stanzschiebers gegenüber dem Führungsschaft, um das chirurgische Stanzinstrument zum Abtrennen einer Gewebe- oder Knochenprobe zu betätigen; und
• - einer ersten Blattfeder wie zuvor beschrieben, die in ihrem Befestigungsabschnitt an dem Handgriff befestigt ist, und einer zweiten Blattfeder wie zuvor beschrieben, die in ihrem Befestigungsabschnitt an dem Betätigungshebel befestigt ist,
• - wobei die erste Blattfeder und die zweite Blattfeder in ihren Kopplungsabschnitten zur Kraftübertragung flexibel miteinander verbunden sind.

In a further aspect, the present invention relates to a surgical punching instrument, in particular a bone punch, for removing a tissue sample, comprising:

• - a guide shaft and a slidable slide mounted thereon;
• a handle fixedly connected to the guide shaft for handling the surgical punching instrument;
• a lever movable relative to the handle for displacing the punch against the guide shaft to actuate the surgical punch to sever a tissue or bone sample; and
• - A first leaf spring as described above, which is fixed in its attachment portion to the handle, and a second leaf spring as described above, which is fixed in its attachment portion on the actuating lever,
• - Wherein the first leaf spring and the second leaf spring are flexibly interconnected in their coupling portions for transmitting power.

Preferred embodiments of the invention are described in the dependent claims. It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the present invention. In particular, the surgical punching instrument or the bone punch can be designed according to the embodiments described for the leaf spring in the dependent claims.

According to the invention, it is provided that a width of the leaf spring in its attachment section in the region of the opening is greater, at least by a diameter of the opening, than a width of the leaf spring in its spring section. Due to the widened fastening portion, a break-out of the leaf spring in the region of attachment to the handle or to the actuating lever is prevented.

The fact that a smaller width or amount of material was provided in this area in previously used leaf springs, this area was particularly susceptible to fatigue fractures or defects. The leaf spring according to the invention specifically increases the stability in this area. The relevant for the exerted spring or restoring force bendable spring portion can be designed in the usual way. Accordingly, the required spring force can be defined within the relevant limits and yet a stable attachment of the leaf spring and a long life can be ensured.

In a preferred embodiment, the opening is formed as a hole, preferably as a circular hole. Usually, the leaf spring is screwed by a screw on the operating lever or on the handle. By using a corresponding screw hole in the mounting portion of the leaf spring, a detachment or slipping is avoided, so that a robust and secure attachment is ensured.

In a preferred embodiment, the width of the leaf spring in the attachment portion and the spring portion is variable. Furthermore, a maximum width of the leaf spring in the attachment portion at least by the diameter of the opening is greater than a minimum width of the leaf spring in the spring section. It is possible that the width of the leaf spring varies within the sections. It is particularly advantageous if the width of the material in the attachment section in the region of the opening is not less than in the spring section. This ensures that there is no fatigue fractures in the attachment section in the region of the opening.

In an advantageous embodiment, the opening in the region of a maximum width of the leaf spring in the attachment portion is arranged. In order to have the lowest possible cost of materials, it is advantageous if the width of the leaf spring is increased only in the region of the opening. The stability is ensured without the use of additional material, by the way, the properties are affected or changed as little as possible with respect to the force exerted by the leaf spring force.

In an advantageous embodiment of the attachment portion is formed in a top view spearhead-shaped and has a rounded taper between mounting portion and spring portion. By the rounded taper is achieved that the broadening in the attachment portion has no or only a slight effect on the properties with respect to the force exerted by the leaf spring. The applied force can be precisely determined by a corresponding design of the spring section. Nevertheless, a long life and a stable attachment can be ensured by the widened attachment portion.

In an advantageous embodiment, the coupling portion comprises a ball joint coupling. Here, a ball joint coupling is understood to mean both a male and a female part of a ball joint. In most cases, two leaf springs are used in a surgical punching instrument, one of which comprises a male part of the ball joint coupling and the other a female part of the ball joint coupling. The ball joint coupling connects both leaf springs flexibly at their coupling sections and ensures a force flow with varying bending.

In an advantageous embodiment, the fastening section, the coupling section and the spring section have a constant thickness. A leaf spring with a constant thickness can be produced efficiently.

In a preferred embodiment of the surgical punching instrument, the coupling portion of the first leaf spring comprises a first ball joint coupling, and the coupling portion of the second leaf spring comprises a second ball joint coupling. The first ball joint coupling and the second ball joint coupling cooperate as a ball joint. By a ball joint, an efficient power transmission between the two leaf springs can be ensured. Here, the two ball joint couplings are not identical, but designed as a female and male part of a ball joint.

In a further advantageous embodiment, the first leaf spring is screwed in its attachment portion to a handle and the second leaf spring is screwed in its attachment portion on the actuating lever. Due to the interaction of the two leaf springs, a provision of the surgical punching instrument is achieved after actuation.

A surgical punching instrument is understood here in particular as a bone punch. A section indicates a part of the leaf spring. It is understood that the transition between two sections does not necessarily have to be spatially exactly defined. Under a fastener is understood in particular a screw. A leaf spring is usually constructed essentially along a longitudinal axis. A width of the leaf spring is an extension in the direction of a transverse axis perpendicular to this longitudinal axis and perpendicular to a bending direction. A thickness is understood to be the thickness of the material (material thickness) perpendicular to the longitudinal axis and to the transverse axis.

• 1 eine schematische Darstellung eines erfindungsgemäßen chirurgischen Stanzinstruments zum Entnehmen einer Gewebeprobe;
• 2 eine schematische Darstellung einer erfindungsgemäßen Blattfeder zum Rückstellen eines chirurgischen Stanzinstruments;
• 3 eine schematische Darstellung einer weiteren Ausführungsform einer erfindungsgemäßen Blattfeder.

The invention will be described in more detail below with reference to some selected embodiments in conjunction with the accompanying drawings and explained. Show it:

• 1 a schematic representation of a surgical punching instrument according to the invention for removing a tissue sample;
• 2 a schematic representation of a leaf spring according to the invention for resetting a surgical punching instrument;
• 3 a schematic representation of another embodiment of a leaf spring according to the invention.

In the 1 is a surgical punching instrument 10 shown. The illustrated embodiment corresponds to a bone punch. By such a surgical punching instrument 10 For medical applications, a human tissue or bone sample may be taken. A physician or a member of the medical professional guides the instrument to a donor site, preferably within the human body. There, the instrument is then actuated to remove the tissue or bone sample.

The illustrated punching instrument 10 has a leadership 12 and one on this leadership 12 slidably mounted punching slide 14 on. With the leadership 12 is a handle 16 firmly connected. The handle 16 allows an application of the surgical punching instrument by the surgeon. To remove the sample, the punch slide 14 towards the leadership 12 postponed. This will sound 18 at the front end of the surgical punch 10 moved against each other and performed a cutting motion. To initiate this shift, one is opposite the handle 16 movable operating lever 20 intended.

To reset the punching instrument 10 After actuation are in the illustrated embodiment, a first leaf spring 22a and a second leaf spring 22b provided by a spring or restoring force between the actuating lever 20 and handle 16 is exercised.

In the illustrated embodiment, the two leaf springs 22a . 22b over a ball joint 24 connected with each other. The ball joint 24 is thereby by a first ball joint coupling 26a on the first leaf spring 22a and a second ball joint coupling 26b on the second leaf spring 22b educated. The first ball joint coupling 26a and the second ball joint coupling 26b are not symmetrical, but designed as interlocking parts. The ball joint couplings 26a . 26b are commonly referred to as a ball and bowl. It is understood that other types of coupling for coupling the two leaf springs 22a . 22b can be provided. For example, a fork coupling or a hinge coupling may be provided. The ball joint 24 has the particular advantage that a release of the two leaf springs 22a . 22b is not possible from each other. This enables a robust application.

In the 2 schematically is a leaf spring according to the invention 22 for resetting a surgical punching instrument after actuation. The representation corresponds to a plan view. The leaf spring 22 is essentially constructed along a longitudinal axis (x-axis in the illustration). Below the width of the leaf spring 22 is the extension in the direction of a transverse axis transverse to the longitudinal axis understood (y-axis). A thickness of the leaf spring indicates an extension orthogonal to the x-axis and y-axis in the illustration. The leaf spring 22 has along its longitudinal axis an attachment portion 28 , a coupling section 30 and a spring section 32 on.

The attachment section 28 is designed to be the leaf spring 22 to attach to the handle or the operating lever of the surgical punch. For this purpose, the attachment section comprises 28 an opening 34 for receiving a fastener, so that the leaf spring 22 can be attached to the handle or the operating lever. In the illustrated embodiment, the opening is formed as a circular hole. In particular, the attachment means may be a screw through which the leaf spring 22 can be screwed.

The coupling section 30 is designed to be the leaf spring 22 to connect with a second leaf spring. For this purpose, the coupling section 30 in the illustrated embodiment, a ball joint coupling 26 on. In the illustration is the ball joint coupling 26 formed as an opening or bowl for receiving a correspondingly large ball portion of a second leaf spring.

The spring section 32 between attachment section 28 and coupling section 30 is bendable. About an elastic deformation of the leaf spring 22 especially in their spring section 32 the spring force is exerted, wherein the spring force is applied substantially perpendicular to the longitudinal and transverse axis. Depending on the width and thickness of the leaf spring 22 in the region of the spring section 32 the applied spring force becomes larger or smaller.

According to the invention, a width b of the leaf spring 22 in its attachment section 28 in the area of the opening 34 at least by a diameter d of the opening greater than a width f of the leaf spring in its spring section 32 , Accordingly, in the region of the opening in the attachment section 28 more material provided so that a fatigue breakage or a breakout in this area is prevented. Compared to previous leaf springs, the leaf spring according to the invention is thus more stable, in particular against a break in the region of the opening.

In the illustrated embodiment, the attachment portion 28 as shown spearhead-shaped. The attachment section 28 tapers on its the spring section 32 opposite side. Between attachment section 28 and spring section 32 there is a rounded rejuvenation on both sides 36 in front. The rounded rejuvenation 36 causes a width of the leaf spring 22 in the spring section 32 can be selected according to the necessary spring force without the width b in the attachment section 28 would be influenced by this. Preferably, the thickness of the leaf spring 22 constant, whereby a simple production is achieved.

In the 3 is an alternative embodiment of a leaf spring according to the invention 22 ' shown schematically. In the coupling section 30 is a fork coupling 38 intended. A fork coupling 38 has tines which engage with tines of the second leaf spring, thus also forming a joint. In the example shown, two prongs are provided, which cooperate with a prong of the second leaf spring. However, other configurations and numbers of tines may be used.

In the attachment section 28 is the opening 34 formed as a hole in the example shown above. The opening may also be formed as an incision in alternative embodiments. The incision can be used for example for mounting on a projection or also on a screw on the actuating lever or on the handle. It is understood that the formation of the attachment portion is substantially independent of the formation of the attachment portion and the different combinations are possible.

In a further embodiment, a hinge joint is provided in the coupling section. The two leaf springs are then rotatable about a rotation axis in the manner of a hinge. In the attachment portion, the opening may be formed as an incision or as a hole.

The invention has been fully described and explained with reference to the drawings and the description. The description and explanation are to be considered as illustrative and not restrictive. The invention is not limited to the disclosed embodiments. Other embodiments or variations will become apparent to those skilled in the art upon use of the present invention and upon a detailed analysis of the drawings, the disclosure, and the following claims.

In the claims, the words "comprise" and "with" do not exclude the presence of other elements or steps. The undefined article "a" or "an" does not exclude the presence of a plurality. A single element or unit may perform the function of several of the units specified in the claims. The mere mention of some measures in several different dependent protection claims is not to be understood that a combination of these measures can not be used equally advantageous. Reference signs in the claims are not intended to be limiting.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 4316768 A1 [0004]

Claims (10)

A leaf spring (22, 22 ', 22a, 22b) for returning a surgical punching instrument (10) after actuation, comprising: an attachment portion (28) for attaching the leaf spring to a handle (16) of the surgical punch or an operative handle (20) of the surgical punch, which is fixed to a guide shaft (12) of the surgical punch, the attachment portion having an opening (Fig. 34) for performing a fastening means for securing the leaf spring to the handle or to the actuating lever; a coupling portion (30) for flexibly connecting the leaf spring to a second leaf spring; and a bendable spring portion (32) between the attachment portion and the coupling portion for applying a spring force so that the operation lever and the handle for returning the surgical punching instrument are led away from each other, wherein a width (b) of the leaf spring in its attachment portion in the region of the opening at least by a diameter (d) of the opening is greater than a width (f) of the leaf spring in its spring portion. Leaf spring (22, 22 ', 22a, 22b) after Claim 1 , wherein the opening (34) is formed as a hole, preferably as a circular hole. A leaf spring (22, 22 ', 22a, 22b) according to any one of the preceding claims, wherein the width of the leaf spring in the mounting portion (28) and in the spring portion (32) is variable; and a maximum width of the leaf spring in the attachment portion at least by the diameter of the opening (34) is greater than a minimum width of the leaf spring in the spring portion. Leaf spring (22, 22 ', 22a, 22b) according to one of the preceding claims, wherein the opening (34) in the region of a maximum width of the leaf spring in the mounting portion (28) is arranged. Leaf spring (22, 22 ', 22a, 22b) according to any one of the preceding claims, wherein the fastening portion (28) is formed in a spearhead shape in a plan view and a rounded taper (36) between the fastening portion and spring portion (32). A leaf spring (22, 22 ', 22a, 22b) according to any one of the preceding claims, wherein the coupling portion (30) comprises a ball joint coupling (26, 26a, 26b). Leaf spring (22, 22 ', 22a, 22b) according to any one of the preceding claims, wherein fastening portion (28), coupling portion (30) and spring portion (32) have a constant thickness. Surgical punching instrument (10), in particular bone punch, for removing a tissue or bone sample, comprising: a guide shaft (12) and a punch slide (14) mounted displaceably thereon; a handle (16) fixedly connected to the guide shaft for handling the surgical punching instrument; an actuating lever (20) movable relative to the handle for displacing the punch slide against the guide shaft for actuating the surgical punching instrument to separate a tissue or bone sample; and a first leaf spring (22a) according to one of Claims 1 to 7 , which is fixed in its attachment portion (28) on the handle, and a second leaf spring (22b) according to one of Claims 1 to 7 which is fixed in its attachment portion to the operating lever, wherein the first leaf spring and the second leaf spring are flexibly connected in their coupling portions (30) for transmitting power. Surgical punching instrument (10) after Claim 8 wherein the coupling portion (30) of the first leaf spring (22a) comprises a first ball joint coupling (26a) and the coupling portion of the second leaf spring (22b) comprises a second ball joint coupling (26b); and the first ball joint coupling and the second ball joint coupling cooperate as a ball joint (24). Surgical punching instrument (10) after one of Claims 8 and 9 wherein the first leaf spring (22a) is screwed in its mounting portion (28) to the handle (16) and the second leaf spring (22b) is screwed in its mounting portion to the actuating lever (20).

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