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.

In general, the pair of spring washers are usually arranged face-to-face and have low rigidity, such that the micro feeding mechanism does not have good rigidity. The micro feeding mechanism will vibrate when cutting a hard material or cutting at a high speed, and thus the quality of the section will not be good enough.

<CIT> discloses a microtome which is provided with a drive wheel mounted in a stand, to be actuated manually and/or by means of a drive motor for generating a vertical relative movement between a specimen holder and a cutting knife, and which has a specimen holder, having a specimen clamping mechanism, arranged so as to be horizontally displaceable in a vertically drivable guide mechanism by means of a cutting-thickness adjustment mechanism. The adjustment mechanism can horizontally displace the specimen holder through a cutting thickness adjustment distance towards the cutting knife. A specimen retraction mechanism serves to displace horizontally the specimen holder from an unretracted position to a retracted position, the retracted position being further from the cutting knife than the unretracted position. The distance between the retracted position and the unretracted position is greater than the maximum cutting thickness adjustment distance.

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 enhances the rigidity of the feeding mechanism and improves the quality of the section.

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

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 for a feeding mechanism of a rotary microtome, including: a spindle movable along an axis direction thereof and having a first end; a support plate having a fixed position, the first end penetrating the support plate; and a plurality of spring washers fitted over the first end and stacked together in an identical direction. The plurality of spring washers are compressed between the spindle and the support plate with a predetermined pre-load. The spindle is configured to be switchable between a first position and a second position, and capable of moving a predetermined distance relative to the support plate in the axis direction of the spindle during switching. When in the first position, the spindle is farthest from the support plate, when in the second position, the spindle is closest to the support plate.

<FIG> illustrate perspective views of a retraction device <NUM> and a feeding mechanism <NUM> according to the embodiment of the present invention, and <FIG> illustrates a partial sectional view of the retraction device <NUM> according to the embodiment of the present invention.

In <FIG>, in order to facilitate the description and the orientation, 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 X axis is a down direction.

As illustrated in <FIG>, the retraction device <NUM> for the feeding mechanism of the rotary microtome according to the embodiment of the present invention includes a spindle <NUM>, a support plate <NUM> and a plurality of spring washers <NUM>.

The spindle <NUM> is movable along an axis direction thereof. The position of the support plate <NUM> is fixed, and a first end of the spindle <NUM> penetrates the support plate <NUM>. The plurality of spring washers <NUM> are fitted over the first end of the spindle <NUM> and stacked together in an identical direction, and the plurality of spring washers <NUM> are compressed between the spindle <NUM> and the support plate <NUM> with a predetermined pre-load. It should be noted that the position of the support plate <NUM> being fixed means that the support plate <NUM> is arranged in a fixed position relative to the spindle <NUM> and the plurality of spring washers <NUM>, such that the support plate <NUM> can support the spindle <NUM> and the plurality of spring washers <NUM>. The plurality of spring washers <NUM> being stacked together in the identical direction means that the plurality of spring washers are oriented in the identical direction and abutted against each other, rather than arranged face-to-face. Besides, the first end of the spindle <NUM> refers to a rear end illustrated in <FIG>.

The spindle <NUM> is switchable between a first position and a second position, and can move a predetermined distance relative to the support plate <NUM> in the axis direction of the spindle <NUM> during switching. In some embodiments, when in the first position, the spindle <NUM> is farthest from the support plate <NUM>. When pulled, the spindle <NUM> can compress the plurality of spring washers <NUM>, and the spindle <NUM> can be moved the predetermined distance towards the support plate <NUM> to the second position along the axis direction of the spindle <NUM>. When in the second position, the spindle <NUM> is closest to the support plate <NUM>. When released, the spindle <NUM> moves the predetermined distance away from the support plate <NUM> to the first position along the axis direction of the spindle <NUM> under the effect of elastic restoring force of the plurality of spring washers <NUM>, thus realizing the retraction and release of the retraction device <NUM>. In some embodiments, the axis direction of the spindle <NUM> refers to a front-and-rear direction illustrated in <FIG>.

It could be understood by those skilled in the related art that the spindle <NUM> can rotate around the axis direction of the spindle <NUM> to drive the micro feed of the feeding mechanism <NUM>. In contrast, the retraction device <NUM> moves the spindle <NUM> along the axis direction of the spindle <NUM> to drive the feeding mechanism <NUM> to retract and release in a small range.

The support plate <NUM> defines an opening (not illustrated), and a part of the first end of the spindle <NUM> protrudes from the opening. The plurality of spring washers are fitted over the first end of the spindle <NUM>, that is, an inner diameter of each spring washer <NUM> is greater than a diameter of the first end of the spindle <NUM>. In addition, an outer diameter of each spring washer <NUM> is greater than the diameter of the opening, such that the plurality of spring washers <NUM> can be abutted against the support plate <NUM>.

As illustrated in <FIG>, the retraction device <NUM> also includes a pull rod <NUM>, and the pull rod <NUM> is connected to the first end of the spindle <NUM>, such that the retraction device <NUM> can be operated. In some embodiments, the pull rod <NUM> is located at a side of the support plate <NUM> away from the spindle <NUM>, such that the retraction device <NUM> can be easily accessed and operated. Further, the pull rod <NUM> may be connected to the first end of the spindle <NUM> in a direction perpendicular to the axis direction of the spindle <NUM>, such that the retraction device <NUM> can be operated more lightly.

As illustrated in <FIG>, three spring washers <NUM> are provided, such that the rigidity of the retraction device <NUM> in the first position along the axis direction of the spindle <NUM> is enhanced and the elastic force of the plurality of spring washers <NUM> is suitable when the spindle <NUM> moves to the second position, which is conducive for the operation of the retraction device <NUM>.

Each spring washer <NUM> may be a disc spring washer, and an inner ring of each disc spring washer has an identical protruding direction. That is, a plurality of disc spring washers are arranged in the identical direction and stacked together, such that a force of the plurality of spring washers <NUM> on the spindle <NUM> is more uniform, and the rigidity of the retraction device <NUM> in the first position along the axis direction of the spindle <NUM> can be further enhanced. Further, the protruding direction of the inner ring of each disc spring washer is directed from the support plate <NUM> to the spindle <NUM>, which is conductive for the spindle <NUM> to restore from the second position to the first position.

The first end of the spindle <NUM> is provided with a flange <NUM>, and the plurality of spring washers <NUM> are compressed between the spindle <NUM> and the support plate <NUM> by the flange <NUM>. The flange <NUM> includes a first flange <NUM> and a second flange <NUM>, the plurality of spring washers <NUM> are fitted over the first flange <NUM> and abut against the second flange <NUM>. That is, an outer diameter of the first flange <NUM> is smaller than the inner diameter of each spring washer <NUM>, and an outer diameter of the second flange <NUM> is greater than the inner diameter of each spring washer <NUM> and smaller than an outer diameter of each spring washer <NUM>, thus ensuring the support for the plurality of spring washers <NUM> and saving materials.

A gap G is defined between an end face of the flange <NUM> adjacent to the support plate <NUM> and the support plate <NUM>, and the gap G is greater than or equal to the predetermined distance that the spindle <NUM> can move during switching between the first position and the second position, such that the movement of the spindle <NUM> along the axis direction of the spindle <NUM> is not interfered. Further, a flat washer <NUM> is arranged between the plurality of spring washers <NUM> and the support plate <NUM>, and the flat washer <NUM> is fitted over the first flange <NUM>, so as to increase a contact area and facilitate defining the gap G. Further, along the axis direction of the spindle <NUM>, a sum of a thickness of the plurality of spring washers <NUM> in the first position and a thickness of the flat washer <NUM> is greater than a thickness of the first flange <NUM>, thus defining the gap G.

A plane bearing <NUM> may be disposed between the plurality of spring washers <NUM> and the support plate <NUM>, and thus the plurality of spring washers <NUM> may rotate with the spindle <NUM>, such that the retraction device <NUM> does not affect the rotation of the spindle <NUM>. That is, the spindle <NUM> can rotate to drive the micro feed of the micro feeding mechanism <NUM>. In some embodiments, the plane bearing <NUM> is arranged between the flat washer <NUM> and the support plate <NUM>, and is fitted over the first end of the spindle <NUM> through a spindle sleeve <NUM>. Thus, the spindle <NUM> can rotate around the axis direction thereof and move along the axis direction thereof.

Referring to <FIG>, the feeding mechanism <NUM> for the rotary microtome 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. A 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 the predetermined distance relative to the first slide base <NUM> in the axis direction of the spindle <NUM>. In some embodiments, the object carriage <NUM> is slidable in the front-and-rear direction relative to the first slide base <NUM>, and the first slide base <NUM> is slidable in an up-and-down direction relative to the second slide base <NUM>. It should be noted that the second slide base <NUM> having a fixed position means that 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.

In addition, the support plate <NUM> may be fixedly connected to or integrally formed with the first slide base <NUM>. Thus, the retraction device <NUM> can be stably supported by the first slide base <NUM>.

It may 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.

The working process of the retraction device <NUM> according to the embodiment of the present disclose is described as follows.

During a section process of a rotary microtome, the feeding mechanism <NUM> drives a specimen to pass through a blade (not illustrated) from top to bottom to complete one section. After the one section, the object carriage <NUM> carried with specimen is located at a position below the blade. During the specimen moves upward to a position above the blade, in order to avoid the blade hitting the specimen surface, the pull rod <NUM> may be pulled to drive the spindle <NUM> to compress the plurality of spring washers <NUM> to deform, such that the spindle <NUM> can move a predetermined distance away from the blade from the first position to the second position along the axis of the spindle <NUM>, and drive the object carriage <NUM> away from the blade. At this time, the first slide base <NUM> is driven to slide upward, and the object carriage <NUM> carried with the specimen is moved back to the position above the blade. The pull rod <NUM> may be released, and under the effect of elastic restoring force, the plurality of spring washers <NUM> push the spindle <NUM> to move toward the blade from the second position back to the first position along the axis of the spindle <NUM>. Thus, the rotary microtome can continue for section.

As illustrated in <FIG>, the retraction device <NUM> according to embodiments of the present invention includes inter alia: a spindle <NUM> movable along an axis direction thereof and having a first end; a support plate <NUM> having a fixed position, the first end of the spindle <NUM> penetrating the support plate <NUM>; and a plurality of spring washers <NUM> fitted over the first end of the spindle <NUM> and stacked together in an identical direction. The plurality of spring washers <NUM> are compressed between the spindle <NUM> and the support plate <NUM> with a predetermined pre-load. The spindle <NUM> is configured to be switchable between a first position and a second position, and capable of moving a predetermined distance relative to the support plate <NUM> in the axis direction of the spindle <NUM> during switching. When in the first position, the spindle <NUM> is farthest from the support plate <NUM>, and when in the second position, the spindle <NUM> is closest to the support plate <NUM>.

In the retraction device <NUM> and the feeding mechanism <NUM> according to the embodiment of the present invention, the retraction device <NUM> has a relatively high rigidity due to the arrangement of the plurality of spring washers <NUM> stacked in the identical direction, which can effectively reduce the vibration and improve the quality of the section when cutting a hard material or cutting at a high speed.

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 invention, "a plurality of" means two or more than two, unless specified otherwise.

In the present invention, unless specified otherwise, terms "mounted", "coupled" "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 invention, 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 "down", "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.

Claim 1:
A retraction device (<NUM>) for a feeding mechanism (<NUM>) of a rotary microtome, comprising:
a spindle (<NUM>) movable along an axis direction thereof and having a first end; and
a support plate (<NUM>) having a fixed position, the first end penetrating the support plate (<NUM>);
wherein the spindle (<NUM>) is configured to be switchable between a first position and a second position, and capable of moving a predetermined distance relative to the support plate (<NUM>) in the axis direction of the spindle (<NUM>) during switching, when in the first position, the spindle (<NUM>) is farthest from the support plate (<NUM>), when in the second position, the spindle (<NUM>) is closest to the support plate (<NUM>),
wherein the first end is provided with a flange (<NUM>), wherein a gap (G) is defined between an end face of the flange (<NUM>) adjacent to the support plate (<NUM>) and the support plate (<NUM>), and wherein the flange (<NUM>) comprises a first flange (<NUM>) and a second flange (<NUM>),
characterized in that, the retraction device (<NUM>) further comprises a plurality of spring washers (<NUM>) fitted over the first end and being compressed between the spindle (<NUM>) and the support plate (<NUM>) with a predetermined pre-load, the spring washers (<NUM>) are stacked together in an identical direction;
the plurality of spring washers (<NUM>) are compressed between the spindle (<NUM>) and the support plate (<NUM>) by the flange (<NUM>); the gap (G) is greater than or equal to the predetermined distance that the spindle (<NUM>) is capable of moving during switching between the first position and the second position; and the plurality of spring washers (<NUM>) are fitted over the first flange (<NUM>) and abut against the second flange (<NUM>); and
the retraction device (<NUM>) comprises a flat washer (<NUM>) arranged between the plurality of spring washers (<NUM>) and the support plate (<NUM>) and fitted over the first flange (<NUM>), whereby a sum of a thickness of the plurality of spring washers (<NUM>) in the first position and a thickness of the flat washer (<NUM>) is greater than a thickness of the first flange (<NUM>).