Patent Description:
In a rotary microtome of the related art, the rotary microtome usually includes an object carriage for carrying a specimen holder which holds a specimen to be cut. The object carriage moves up and down in a vertical path of the rotary microtome. During the vertical movement, the specimen passes through a cutter fixedly arranged on the rotary microtome from an upper position to complete one section. After one section, the specimen holder is located under the cutter.

When the specimen is moved back to the upper position, its surface will hit the cutter and the specimen may be damaged. Therefore, a micro feeding mechanism for the rotary microtome has a retraction device. The function is realized by a pair of spring washers and a pull rod. When retraction is needed, the pull rod is pulled to pull the feeding mechanism back, and when the retraction is not needed, the pull rod is released, such that the feeding mechanism is moved to an original position by the pair of spring washers. The micro feeding mechanism in the related art refers to that the micro feeding mechanism can drive the specimen to feed <NUM> to <NUM> by turning a handwheel one circle.

A movable step realizes a switch between pulling back and releasing of the pull rod by abutting against the pull rod at either a high point or a low point of the movable step. When the retraction is needed, the high point of the movable step abuts against the pull rod such that the pull rod pulls the feeding mechanism back, and when the retraction is not needed, the low point of the movable step abuts against the pull rod such that the pull rod is moved to its original position. The movable step switches the pull rod between the high point and the low point of the movable step by hitting an upper end piece and a lower end piece.

Due to a large step height between the high point and the low point of the movable step, a surface connecting the high point and the low point is too steep and the end pieces are too hard, a current retraction device has a large noise during operation.

<CIT> discloses a retracting mechanism of a slicing machine. The retracting mechanism includes an elastic piece, a retracting control block, a fixed disk, a sliding limiting piece, an upper jacking block and a lower jacking block; the elastic piece is located between a mounting plate and a limiting ring; the retracting control block is externally sleeved on a lead screw; one side of the retracting control block is hinged to the mounting plate; the fixed disk is fixed relative to the lead screw; the sliding limiting piece is provided with a groove matched with a control rod of the retracting control block; the depth of the upper part of the groove is greater than that of the lower part of the groove; the upper jacking block is used to allow the control rod to be located at the upper part of the groove; and the lower jacking block is used to allow the control rod to be located at the lower part of the groove, and drives the retracting control block to rotate. According to the retracting mechanism, after a movable seat moves down to the lowest point, the lead screw can be retracted, blade sticking is prevented, and a sample and a blade can be protected effectively.

The present invention aims to solve at least one of the technical problems in the related art to a certain extent.

To this end, one objective of the present invention is to propose a retraction device which effectively reduces the noise of the retraction device during operation.

Another objective of the present invention is to propose a feeding mechanism having the above retraction device.

The present invention is defined in the independent claims, and the preferable features according to the present invention are defined in the dependent claims.

The embodiments of the present invention are described below with reference to the accompanying drawings. It should be noted that terms "up", "down", "left", "right", "front", "rear" and similar expressions used herein are only for the purpose of explanation, and cannot be construed as the limitation of the present invention.

The present invention relates to a retraction device according to claim <NUM>.

<FIG> illustrates a perspective view of a retraction device and a feeding mechanism according to an embodiment of the present invention. <FIG> illustrates a schematic view of an operating unit according to an embodiment of the present invention, in which the operating unit is in a retraction position. <FIG> illustrates a schematic view of an operating unit according to an embodiment of the present invention, in which the operating unit is in a release position. <FIG> illustrates a schematic view of a movable member according to an embodiment of the present invention.

In <FIG>, in order to facilitate the description and the orientation, an orthogonal XYZ axes are illustrated. A positive direction of X axis is a left direction, while a negative direction of X axis is a right direction; a positive direction of Y axis is a front direction while a negative direction of Y axis is a rear direction; a positive direction of Z axis is an up direction, while a negative direction of Z axis is a down direction.

As illustrated in <FIG>, a retraction device <NUM> for a feeding mechanism of a rotary microtome according to the embodiment of the present invention includes a spindle <NUM> and an operating unit <NUM>.

The spindle <NUM> is movable along an axis direction thereof. The operating unit <NUM> is configured such that the spindle <NUM> is switchable between a retraction position and a release position, and the spindle <NUM> can move a predetermined distance towards or away from the operating unit <NUM> along an axis direction of the spindle <NUM> during the switching. In some embodiments, when in the release position, the spindle <NUM> is in the foremost position, by pulling the spindle <NUM> through the operating unit <NUM>, the spindle <NUM> can move a predetermined distance towards the operating unit <NUM> to the retraction position along the axis direction of the spindle <NUM>. When in the retraction position, the spindle <NUM> is in the rearmost position, by releasing the spindle <NUM> through the operating unit <NUM>, the spindle <NUM> moves away a predetermined distance from the operating unit <NUM> to the release position along the axis direction of the spindle <NUM>, thereby realizing the retraction and release of the retraction device <NUM>. In some embodiments, the axis direction of the spindle <NUM> herein refers to a front-and-rear direction illustrated in <FIG>.

It could be understood by those skilled in the related art that the retraction device <NUM> may be used to drive the retraction and release of the feeding mechanism <NUM> by moving the spindle <NUM> along the axis direction of the spindle <NUM>.

The operating unit <NUM> includes a pull rod <NUM> and a movable member <NUM>. The pull rod <NUM> is a columnar shape extending along a left-and-right direction, and a first end of the pull rod <NUM> is connected to a first end of the spindle <NUM>, such that the spindle <NUM> may be moved along the axis direction of the spindle <NUM> through the pull rod <NUM>. Further, the pull rod <NUM> may be connected to the first end of the spindle <NUM> along a direction perpendicular to the axis direction of the spindle <NUM>, such that the pull rod <NUM> can move the spindle <NUM> more lightly. In some embodiments, the first end of the pull rod <NUM> herein refers to a left end illustrated in <FIG>, and the first end of the spindle <NUM> herein refers to a rear end illustrated in <FIG>.

The movable member <NUM> defines a step-shaped groove <NUM>, and a second end of the pull rod <NUM> is received in the groove <NUM>. In some embodiments, the second end of the pull rod <NUM> herein refers to a right end illustrated in <FIG>. The groove <NUM> includes a first step <NUM>, a second step <NUM> and an inclined face <NUM> connecting the first step <NUM> and the second step <NUM> that are arranged along a first direction (the first step <NUM>, the second step <NUM> and the inclined face <NUM> are illustrated in <FIG>), and a height of the second step <NUM> is greater than a height of the first step <NUM> in the axis direction of the spindle <NUM>. In some embodiments, the first direction herein refers to an up-and-down direction illustrated in <FIG>, and the first step <NUM> is located above the second step <NUM>.

The movable member <NUM> is slidable relative to the pull rod <NUM> in the first direction, such that the pull rod <NUM> is switchable between the first step <NUM> and the second step <NUM> through the inclined face <NUM>, thereby reducing the noise of the retraction device <NUM> during operation. In some embodiments, when in the retraction position, the pull rod <NUM> is received in the second step <NUM>, and when in the release position, the pull rod <NUM> is received in the first step <NUM>.

The retraction device <NUM> may also include an elastic member (not illustrated) disposed between the spindle <NUM> and the operating unit <NUM> with a predetermined pre-load, such that when the spindle <NUM> is pulled, the spindle <NUM> compresses the elastic member to move to the retraction position, and when the spindle <NUM> is released, the spindle <NUM> moves back to the release position under an elastic restoring force of the elastic member.

The operating unit <NUM> further includes a sliding groove member <NUM>, the sliding groove member <NUM> extends in the first direction and is fixedly connected to the pull rod <NUM>, and the movable member <NUM> is received in the sliding groove member <NUM>, such that the movable member <NUM> is slidable relative to the sliding groove member <NUM> and the pull rod <NUM>.

As illustrated in <FIG>, the operating unit <NUM> also includes a first end piece <NUM> and a second end piece <NUM>. The first end piece <NUM> and the second end piece <NUM> have fixed positions and are disposed opposite each other in the first direction, and the movable member <NUM> and the pull rod <NUM> are disposed between the first end piece <NUM> and the second end piece <NUM>. It should be noted that the first end piece <NUM> and the second end piece <NUM> having fixed positions refer to the first end piece <NUM> and the second end piece <NUM> are arranged in a fixed position relative to the pull rod <NUM> and the movable member <NUM>. In some embodiments, the first end piece <NUM> is located above the second end piece, and the movable member <NUM> and the pull rod <NUM> are movable relative to the first end piece <NUM> and the second end piece <NUM> in the up-and-down direction, such that the first end piece <NUM> and the second end piece <NUM> define limit positions of movement of the movable member <NUM> along the up-and-down direction. Thus, the movable member <NUM> hits the first end piece <NUM> or the second end piece <NUM>, such that sliding of the movable member <NUM> relative to the pull rod <NUM> can be realized, that is, switching of the pull rod <NUM> between the first step <NUM> and the second step <NUM> is realized.

The first end piece <NUM> and the second end piece <NUM> may be made of a material with low Shore hardness, such as plastic, rubber, etc. In some embodiments, the first end piece <NUM> and the second end piece <NUM> may be made of a material with a Shore hardness of <NUM> to <NUM>, in some embodiments, a material with a Shore hardness of <NUM>, thereby further reducing the noise of the retraction device <NUM> during operation.

As illustrated in <FIG>, when in the retraction position, a lower end face <NUM> of the movable member <NUM> abuts against an upper surface <NUM> of the second end piece <NUM>, and the pull rod <NUM> is received in the second step <NUM>.

As illustrated in <FIG>, when in the release position, an upper end face <NUM> of the movable member <NUM> abuts against a lower surface <NUM> of the first end piece <NUM>, and the pull rod <NUM> is received in the first step <NUM>.

As illustrated in <FIG>, the first step <NUM> includes a first flat face <NUM>, a first cylinder face <NUM> and a second flat face <NUM>. A radius of the first cylinder face <NUM> is configured to suitably receive the pull rod <NUM>. In some embodiments, the radius of the first cylinder face <NUM> is equal to a radius of the pull rod <NUM>. It should be understood that the radius of the first cylinder face <NUM> may also be greater than the radius of the pull rod <NUM>. The first flat face <NUM> extends along the axis direction of the spindle <NUM> and is tangentially connected to the first cylinder face <NUM>, and the second flat face <NUM> extends along the first direction and is tangentially connected to the first cylinder face <NUM>. It may be understood that the first flat face <NUM> is perpendicular to the second flat face <NUM>. A length of the first flat face <NUM> along the axis direction of the spindle <NUM> and a length of the second flat face <NUM> along the first direction are respectively suitable for receiving the pull rod <NUM> to prevent the pull rod <NUM> from escaping. In some embodiments, the length of the first flat face <NUM> along the axis direction of the spindle <NUM> and the length of the second flat face <NUM> along the first direction are respectively greater than a diameter of the pull rod <NUM>. Further, the length of the first flat face <NUM> along the axis direction of the spindle <NUM> may be equal to the length of the second flat face <NUM> in the first direction.

The second step <NUM> includes a third flat face <NUM>, a second cylinder face <NUM> and a fourth flat face <NUM>. A radius of the second cylinder face <NUM> is configured to suitably receive the pull rod <NUM>. In some embodiments, the radius of the second cylinder face <NUM> is equal to a radius of the pull rod <NUM>. It should be understood that the radius of the second cylinder face <NUM> may also be greater than the radius of the pull rod <NUM>. The third flat face <NUM> extends along the axis direction of the spindle <NUM> and is tangentially connected to the second cylinder face <NUM>, and the fourth flat face <NUM> extends along the first direction and is tangentially connected to the second cylinder face <NUM>. It may be understood that the third flat face <NUM> is perpendicular to the fourth flat face <NUM>. A length of the third flat face <NUM> along the axis direction of the spindle <NUM> and a length of the fourth flat face <NUM> along the first direction are respectively suitable for receiving the pull rod <NUM> to prevent the pull rod <NUM> from escaping. In some embodiments, the length of the third flat face <NUM> along the axis direction of the spindle <NUM> and the length of the fourth flat face <NUM> along the first direction are respectively greater than or equal to the diameter of the pull rod <NUM>. Further, the length of the third flat face <NUM> along the axis direction of the spindle <NUM> is equal to the length of the fourth flat face <NUM> in the first direction. It could be understood that the length of the third flat face <NUM> along the axis direction of the spindle <NUM> is shorter than the length of the first flat face <NUM> along the axis direction of the spindle <NUM>.

The inclined face <NUM> connects a lower edge of the second flat face <NUM> and an upper edge of the fourth flat face <NUM>. An inclined angle A of the inclined face <NUM> relative to the first direction ranges from <NUM>° to <NUM>°, and in one embodiment, the inclined angle A is <NUM>°. A length of the inclined face <NUM> along the axis direction of the spindle <NUM>, i.e. a height difference H between the first step <NUM> and the second step <NUM> ranges from <NUM> to <NUM>. In one embodiment, the height difference H is <NUM>. The length L of the inclined face <NUM> along the first direction ranges from <NUM> to <NUM>, and in one embodiment the length L is <NUM>. Therefore, such arrangement of the inclined face <NUM> can further reduce the noise of the retraction device <NUM> during operation.

Referring to <FIG>, the working process of the retraction device <NUM> according to embodiments of the invention is described as follows.

As illustrated in <FIG>, the retraction device <NUM> is in the retraction position, the lower end face <NUM> of the movable member <NUM> abuts against the upper surface <NUM> of the second end piece <NUM>, the pull rod <NUM> is received in the second step <NUM>, and the pull rod <NUM> abuts against the fourth flat face <NUM>. In order to release the spindle <NUM>, the pull rod <NUM> may be moved upward. Due to the effect of the elastic member, the pull rod <NUM> is compressed in the second step <NUM>, and the movable member <NUM>, the sliding groove member <NUM> and the pull rod <NUM> move upward together. When the upper end face <NUM> of the movable member <NUM> abuts against the lower surface <NUM> of the first end piece <NUM>, the movable member <NUM> cannot move upward any more, and the sliding groove member <NUM> and the pull rod <NUM> still move upward together. Due to the effect of the elastic member, the pull rod <NUM> moves from the second step <NUM> to the first step <NUM> along the inclined face <NUM>, and the pull rod <NUM> moves forward, so as to drive the spindle <NUM> to move forward for a predetermined distance to return to the release position.

As illustrated in <FIG>, the retraction device <NUM> is in the release position, the upper end face <NUM> of the movable member <NUM> abuts against the lower surface <NUM> of the first end piece <NUM>, the pull rod <NUM> is received in the first step <NUM>, and the pull rod <NUM> abuts against the second flat face <NUM>. In order to retract the spindle <NUM>, the pull rod <NUM> may be moved downward. Due to the effect of the elastic member, the pull rod <NUM> is compressed in the first step <NUM>, and the movable member <NUM>, the sliding groove member <NUM> and the pull rod <NUM> move downward together. When the lower end face <NUM> of the movable member <NUM> abuts against the upper surface <NUM> of the second end piece <NUM>, the movable member <NUM> cannot move downward any more, and the sliding groove member <NUM> and the pull rod <NUM> still move downward together. Due to the effect of the elastic member, the pull rod <NUM> moves from the first step <NUM> to the second step <NUM> along the inclined face <NUM>, and the pull rod <NUM> moves backward, so as to drive the spindle <NUM> to move backward for a predetermined distance to return to the retraction position.

Referring to <FIG>, the feeding mechanism <NUM> according to the embodiment of the present invention includes an object carriage <NUM>, a first slide base <NUM>, a second slide base <NUM> and a retraction device <NUM> according to the above embodiments.

The object carriage <NUM> is slidably connected to the first slide base <NUM>, the first slide base <NUM> is slidably connected to the second slide base <NUM>, and the second slide base <NUM> has a fixed position. The second end of the spindle <NUM> of the retraction device <NUM> is connected to the object carriage <NUM>, and configured to drive the object carriage <NUM> to retract a predetermined distance relative to the first slide base <NUM> along the axis direction of the spindle <NUM>. In some embodiments, the object carriage <NUM> is slidable relative to the first slide base <NUM> along the front-and-rear direction, and the first slide base <NUM> is slidable relative to the second slide base <NUM> along the up-and-down direction. It should be noted that the second slide base <NUM> having a fixed position refers to the second slide base <NUM> is arranged in a fixed position relative to the first slide base <NUM>, the object carriage <NUM> and the retraction device <NUM>, so as to be able to support these components.

It could be understood that other structures and principles of the feeding mechanism <NUM> are accessible for those skilled in the related art, which will not be repeated herein.

As illustrated in <FIG>, in some embodiments, the retraction device <NUM> according to the embodiments of the present invention includes a spindle <NUM> that is movable along an axis direction thereof and has a first end; and an operating unit <NUM> which includes a pull rod <NUM> and a movable member <NUM>. The pull rod <NUM> has a first end and a second end, the movable member <NUM> defines a step-shaped groove <NUM>, the first end of the pull rod <NUM> is connected to the first end of the spindle <NUM>, the second end of the pull rod <NUM> is received in the groove <NUM>. The groove <NUM> includes a first step <NUM>, a second step <NUM> and an inclined face <NUM> connecting the first step <NUM> and the second step <NUM> that are arranged along a first direction, and a height of the second step <NUM> is greater than a height of the first step <NUM> in the axis direction of the spindle <NUM>. The movable member <NUM> is slidable relative to the pull rod <NUM> in the first direction, such that the pull rod <NUM> is switchable between the first step <NUM> and the second step <NUM> through the inclined face <NUM>, and thus the spindle <NUM> is switchable between a retraction position and a release position. When in the retraction position, the pull rod <NUM> is received in the second step <NUM>, and when in the release position, the pull rod <NUM> is received in the first step <NUM>.

In the retraction device <NUM> and the feeding mechanism <NUM> according to the embodiments of the present invention, the arrangement of the inclined face <NUM> connecting the first step <NUM> and the second step <NUM> effectively avoids the hit between components of the retraction device <NUM> during the operation, thereby effectively reducing the noise of the retraction device <NUM> during operation.

In addition, terms such as "first" and "second" are used herein for purposes of description and are not intended to indicate or imply relative importance or significance or to imply the number of indicated technical features. Thus, the feature defined with "first" and "second" may include one or more of this feature. In the description of the present disclosure, "a plurality of" means two or more than two, unless specified otherwise.

In the present disclosure, unless specified otherwise, terms "mounted", "couple" "connected", "fixed" and the like are used broadly. For example, fixed connections, detachable connections, or integral connections; may also be mechanical or electrical connections or direct connections, or indirect connections via intervening structures; may also be inner communications or interactions of two elements, which can be understood by those skilled in the art according to specific situations.

In the descriptions of the present disclosure, it should be noted that, unless otherwise expressly specified and limited, the first feature "on" or "under" the second feature may be that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature "on", "above" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely be that the first feature has a level higher than the second feature. The first feature "below", "under" and "on bottom of" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely be that the first feature has a level less than the second feature.

Reference throughout this specification to terms "an embodiment," "some embodiments," "an example", "a specific example," or "some examples," means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, exemplary descriptions of aforesaid terms are not necessarily referring to the same embodiment or example. Moreover, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, in the case of non-contradiction, those skilled in the art may combine and group the different embodiments or examples described in this specification and the features of the different embodiments or examples.

Claim 1:
A retraction device (<NUM>) for a feeding mechanism (<NUM>) of a microtome, comprising:
a spindle (<NUM>) movable along an axis direction thereof and having a first end; and
an operating unit (<NUM>) comprising a pull rod (<NUM>) and a movable member (<NUM>), the pull rod (<NUM>) having a first end and a second end, the movable member (<NUM>) defining a step-shaped groove (<NUM>), the first end of the pull rod (<NUM>) being connected to the first end of the spindle (<NUM>), the second end of the pull rod (<NUM>) being received in the groove (<NUM>); the groove (<NUM>) comprising a first step (<NUM>), a second step (<NUM>) and an inclined face (<NUM>) connecting the first step (<NUM>) and the second step (<NUM>) arranged along a first direction, and a height of the second step (<NUM>) being greater than a height of the first step (<NUM>) in the axis direction of the spindle (<NUM>);
wherein the movable member (<NUM>) is slidable relative to the pull rod (<NUM>) in the first direction, such that the pull rod (<NUM>) is switchable between the first step (<NUM>) and the second step (<NUM>) through the inclined face (<NUM>), and thus the spindle (<NUM>) is switchable between a retraction position and a release position; when in the retraction position, the pull rod (<NUM>) is received in the second step (<NUM>), and when in the release position, the pull rod (<NUM>) is received in the first step (<NUM>),
characterized in that the first direction is perpendicular to the axis direction of the spindle (<NUM>);
the inclined angle of the inclined face (<NUM>) relative to the first direction ranges from <NUM>° to <NUM>°; and
the length of the inclined face (<NUM>) along the first direction ranges from <NUM> to <NUM>.