Patent Application
20120043405
This invention relates to a grinding system and more particularly to such a system with a modular pestle assembly for receiving a number of different pestle tips and collars with use in multiple tube configurations for a variety of applications, i.e. research, clinical, industrial.
Grinders are widely used to grind up small quantities of material for further processing and analysis. A container acting as a mortar has a grinding surface in the interior of its base usually conical or rounded in shape for receiving the grinding material. A pestle which is received in the container has a similarly shaped grinding surface and a cap is sealing engaged with the pestle shaft and the top of the container. Often the pestle is made in two or more parts which requires an assembly step and more importantly introduces the opportunity for misalignment of the pestle shaft during assembly. This can result in misalignment of the grinding surfaces and poor grinding results. Another issue is the complexity of the sealing of the cap with the container. Typically the cap requires an intricate sealing structure at its periphery for sealingly engaging the container and another device at its center for sealingly engaging the pestle shaft. A further issue arises because a number of different sizes are needed. Offering grinders of a number of different sizes require not only a number of different size containers but a number of different pestles with a number of different matching sizes of grinding tips. Another problem encountered when the pestle tip is made of one solid piece is “sinking”. Sinking is the dimpling or concavity which occurs in thick molded parts where cooling causes shrinkage resulting in surface sinking. This is critical when it occurs in the grinding surface area of the tip. Presently attempts to prevent sinking require extra manufacturing steps including a water bath.
It is therefore an object of this invention to provide an improved grinding system.
It is a further object of this invention to provide such an improved grinding system with improved grinding performance.
It is a further object of this invention to provide such an improved grinding system with improved grinding performance in multiple configurations.
It is a further object of this invention to provide such an improved grinding system in which the pestle is straight, properly aligned with its grinding surface and with the grinding surface in the container.
It is a further object of this invention to provide such an improved grinding system which has an effective, less complex sealing arrangement between the cap and container and between the cap and pestle.
It is a further object of this invention to provide such an improved grinding system which is simpler, less expensive, easier to manufacture and capable of providing different sizes of pestle grinding tips but using a universal or common pestle shaft.
It is a further object of this invention to provide such an improved grinding system which is modular and can provide a number of different pestle grinding tips using the same pestle shaft.
It is a further object of this invention to provide such an improved grinding system in which the tip and collar can be made hollow to prevent sinking and reduce the cost of materials.
The invention results from the realization that an improved, modular grinding system which is simpler, easier and less expensive can be achieved using a modular pestle assembly including a universal pestle shaft having at its proximate end an actuator portion extending above the top portion of the container and at its distal end a mounting portion for receiving sets of pairs of matching pestle tips and pestle collars. A closure device sealingly engages with the pestle assembly and the top of the container to define a collection chamber.
The subject invention, however, in other embodiments, need not achieve all these objectives and the claims hereof should not be limited to structures or methods capable of achieving these objectives.
This invention features a grinding system including a mortar container having an open top portion and a bottom portion having a first interior grinding surface and a wall portion interconnecting the top and bottom portions for defining a hollow interior collection chamber. A modular pestle assembly includes a universal pestle shaft having at its proximate end an actuator portion extending above the top portion and at its distal end a mounting portion for receiving one of a set of pairs of matching tips and pestle collars, the pestle tip having a second grinding surface for engaging the first grinding surface. A closure device sealingly engageable with the pestle assembly and the open top portion seals the container and the collection chamber between the grinding surfaces and the top portion of the mortar container.
In a preferred embodiment the material ground may be tissue; each pestle collar may include a mounting hole for engaging the pestle shaft and the mounting portion may include a collar stop element for defining the position of the collar on the pestle shaft. Each pestle tip may include a drive hole and the distal end of the pestle shaft may include a drive stub for engaging the drive hole for rotating the pestle tip and the second grinding surface relative to the first grinding surface. The pestle tip may be substantially solid except for the drive hole. The pestle tip may be substantially hollow except for a hub containing the drive hole. Each collar may have an edge engaging a congruent edge of the associated pestle tip. Each pestle collar and tip may be joined at the edges. The pestle collar may have an inclined wall extending from the mounting hole to the edge of the collar for shedding grinding medium downwardly toward the grinding surfaces. The closure may include a cap engaged with the open top portion of the container and the cap may include a resilient sealing member for sealing between the cap and the top portion of the container and between the cap and the pestle assembly. The pestle shaft may include an upper cap stop element for limiting movement of the pestle shaft into the container. The pestle shaft may include a lower cap stop element for limiting movement of the pestle shaft out of the container.
Other objects, features and advantages will occur to those skilled in the art from the following description of a preferred embodiment and the accompanying drawings, in which:
Aside from the preferred embodiment or embodiments disclosed below, this invention is capable of other embodiments and of being practiced or being carried out in various ways. Thus, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings. If only one embodiment is described herein, the claims hereof are not to be limited to that embodiment. Moreover, the claims hereof are not to be read restrictively unless there is clear and convincing evidence manifesting a certain exclusion, restriction, or disclaimer.
The grinding system of this invention may be used in a number of different applications such as plant research, mineral research, pharmaceutical research, (e.g. tablets), wood pulp, animal research and with human tissue, bone and cartilage. One of the more likely uses is for tissue grinding and the embodiment described here will be directed to that.
There is shown in
A second lower cap stop 68,
The universality of pestle assembly 30 and its use in a modular system can be better understood with reference to
Although specific features of the invention are shown in some drawings and not in others, this is for convenience only as each feature may be combined with any or all of the other features in accordance with the invention. The words “including”, “comprising”, “having”, and “with” as used herein are to be interpreted broadly and comprehensively and are not limited to any physical interconnection. Moreover, any embodiments disclosed in the subject application are not to be taken as the only possible embodiments.
In addition, any amendment presented during the prosecution of the patent application for this patent is not a disclaimer of any claim element presented in the application as filed: those skilled in the art cannot reasonably be expected to draft a claim that would literally encompass all possible equivalents, many equivalents will be unforeseeable at the time of the amendment and are beyond a fair interpretation of what is to be surrendered (if anything), the rationale underlying the amendment may bear no more than a tangential relation to many equivalents, and/or there are many other reasons the applicant can not be expected to describe certain insubstantial substitutes for any claim element amended.
Other embodiments will occur to those skilled in the art and are within the following claims.
