1. Technical Field
The present invention is directed to a blade assembly. More particularly, the invention is directed to a novel blade assembly for use in a slicing machine, and to a slicing machine that incorporates the novel blade assembly.
2. Background Information
Many slicing machines are commercially available for slicing food products, such as produce. Currently there are two general types of produce slicers that have blade assemblies made up of multiple blades. One type has a blade set that comprises a plurality of blades that are individually installed into the machine in a loose condition. The individual blades are placed in tension by tightening screws against receiving members positioned along the frame of the machine. This is the most common style of machine presently available. However, this machine requires a heavy, strong frame that is capable of withstanding the initial blade tension and the additional tensile load that results from the cutting action. In addition, this construction is inconvenient for the user when worn or damaged blades must be replaced. In order to replace such blades, the individual blades must be removed from the frame. This action requires sufficient mechanical aptitude to ensure that the blades are safely and properly removed, and also requires that appropriate tools and replacement blades are readily available to enable the task to be successfully completed.
The second type of produce slicer is comparatively new in the marketplace, and is primarily used to slice tomatoes. This type has a unitized blade system, in which the blades are under tension within a frame, separate from the machine into which it the blade system is to be mounted. Machines of this type, to date, have unitized blade systems that are not repairable. These blade systems have inefficient material usage as they are generally machined from a single block of material, from which material is removed from the inner portion of the block to provide the frame. This generates material waste and results in increased costs for replacement. These blade systems require extensive and difficult machining during manufacture. Additionally, the cutting machine must be precisely formed to be able to accept and properly position the blade system. These shortcomings result in increased manufacturing costs for such devices.
It is desired to provide a food slicer having a blade assembly that is readily removable and replaceable in the food slicer, and in which the blades in the blade assembly may be replaced. It is further desired to provide a food slicer that may be readily repaired if desired, that may be utilized with a relatively light weight slicing machine, and that may be produced at a low cost.
The present invention addresses the problems associated with prior art slicers. In one form thereof, the present invention comprises a blade assembly for use in a slicing device. The inventive blade assembly includes a plurality of blades and a pair of tension members, each tension member having a plurality of slots formed therein. The tension members are positioned such that the slots in one tension member are disposed generally opposite the slots in the other tension member, and are spaced such that a longitudinal end of a blade is received in each of the generally opposite slots in a manner such that the blade is maintained between the tension members under tension. A retainer is associated with each of the tension members for retaining a respective blade longitudinal end in the tension member slot. A spacer is provided for maintaining the spacing between the tension members to maintain the blade tension.
The present invention, in another form thereof, comprises a method for forming a blade assembly. In the inventive method, a pair of tension members is initially provided. Each tension member has a plurality of blade-receiving slots formed therein, an opening for receiving a spacer, and a hole longitudinally extending through at least a portion of the tension member, which hole passes through the blade-receiving slots. The tension members are aligned such that the blade-receiving slots in each tension member face each other. A plurality of cutting blades is provided, each blade having opposing longitudinal ends and having an aperture at each of the longitudinal ends. One longitudinal end of each blade is inserted into a respective blade-receiving slot in one tension member, and the other longitudinal end of each blade is inserted into the opposing blade-receiving slot in the other tension member in a manner such that the blade apertures are aligned with the hole extending through a respective tension member. A respective elongated member is inserted through each tension member hole and aligned blade aperture. The tension members having the blades inserted therein are aligned in a fixture, and the fixture is activated to controllably increase the spacing between the tension members to establish a tension in the blades, and to create sufficient distance between the tension members such that a spacer can be inserted between corresponding spacer openings to maintain a desired spacing. A spacer having sufficient strength for maintaining a selected distance between the tension members is inserted into the spacing between opposing tension members. The fixture is then adjusted to allow the tension members to move toward each other a specified distance to seat the spacer in the corresponding spacer openings, and to maintain a desired tension in the blades.
The present invention, in still another form thereof, comprises a food slicing device. The food slicing device comprises a frame, and a blade assembly removably receivable in the frame. The blade assembly includes a plurality of blades, and a pair of tension members. Each tension member has a plurality of blade-receiving slots formed therein. The tension members are positioned such that the slots in one tension member are disposed generally opposite the slots in the other tension member, and are spaced such that a longitudinal end of a blade is received in each of said generally opposite slots and maintained therein under tension. A retainer associated with each of the tension members retains a blade longitudinal end in a tension member slot. A spacer maintains the spacing between the tension members in a manner to maintain the tension in the blades.
For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the figures, and specific language will be used to describe the same. It should nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
Blade assembly 10 includes a plurality of blades 30 mounted therein. Blades 30 span the distance between two opposing tension blocks 14, 16. An example of a suitable tension block is shown in
Preferably, tension blocks 14, 16 are identical to each other, differing only in their relative position in the blade assembly. Thus, in the following discussion of the tension blocks, the same reference numeral is used to describe the corresponding feature in each tension block. A longitudinal hole 18 is extruded or otherwise cut through each of the respective tension blocks 14, 16. Longitudinal holes 18 are sized to receive a tension rod 28, in a manner to be discussed hereinafter. In a preferred embodiment, each tension block 14, 16 also includes another hole 20. Holes 20 may be machined or otherwise formed in each of the respective tension blocks 14, 16, and are provided for mounting blade assembly 10 to a suitable slicing device, such as food slicer 50 shown in
Tension blocks 14, 16 are also provided with a plurality of narrow slots 22 for receiving the end of a blade. Additionally, at each axial end of the tension blocks, a wider slot 24 is provided for receiving a tension bar. The use of narrow slots 22 and wider slots 24 in forming blade assembly 10 will be discussed hereinafter. Although there are many possible ways to form tension blocks 14, 16, it is preferred to form them from a generally-solid blank. The blank may be initially extruded to have the general dimensions shown in
Blade assembly 10 includes a plurality of blades 30 that span the tension blocks 14, 16. The number of blades 30 in a particular blade assembly may be varied according to the slice thickness desired for the food product, such as produce, to be sliced. Preferably, however, the overall outside dimensions of blade assembly 10 will be constant for a particular cutting machine, regardless of the number of blades in the blade assembly. As a result, a cutting machine into which blade assembly 10 is to be inserted, such as produce slicer 50 illustrated in
In order to accommodate different numbers of blades, the tension blocks are generally machined such that the number of slots 22 in the tension block corresponds to the number of blades in the blade assembly. Thus, for example, if it is desired to provide a blade assembly having nine blades spaced, e.g., ⅜ inch apart, then the tension block may be machined to include nine slots 22. This is the arrangement shown in
Blades 30 may have any configuration common for use on food slicers. One example of a suitable blade 30 is illustrated in
The following discussion describes a preferred method for forming a blade assembly 10. Initially, tension blocks 14, 16 are placed on a surface with the blade slots 22 facing one another. When present, the grooves are oriented on the underside of the tension blocks. Blades 30 are then inserted in the properly aligned tension blocks in a manner such that each longitudinal end of a blade fits into a corresponding slot in one of the opposing tension blocks. Tension blocks 14, 16 and blades 30 are aligned such that aperture 33 of each respective blade 30 is aligned with longitudinal hole 18 of tension block 16, and aperture 34 of each respective blade 30 is aligned with longitudinal hole 18 of tension block 14. A suitable mechanism is provided to retain the blade ends in the tension blocks. In the preferred embodiment shown, this mechanism comprises a tension rod 28 (
At this point the blades are fixed in the blade assembly in a loose manner, i.e., there is very little tension in the blades. The cutting ability of such loosely-fixed blades would be considerably inferior when compared to blades fixed in an assembly under tension. In general, the more tension that is created on a blade, the better the cutting ability of the blade. Thus, in order to create tension in the blades, the blade assembly is placed on a fixture from which a suitable amount of tension on the blades may be created. One example of a fixture 66 suitable for such use is illustrated in
As crank 69 of the fixture is rotated, the distance between the respective jaws increases. This increases the distance between respective tension blocks 14, 16, thereby “stretching” the blades and creating a tension therein. Preferably, the distance between tension blocks 14, 16 increases until the elastic limit of the blades is approached. At this point, the distance between the tension blocks 14, 16 is such that tension bars 26 can be inserted therebetween. In the example shown, the tension bars are inserted into tension bar cut-outs 24 at each end of blade assembly 10. Tension bars 26 are preferably formed of a metal block, such as 2024 aluminum, having sufficient strength to withstand the stresses created after fixture 66 is removed, and preventing the blades 30 from relaxing from their tensioned state. Those skilled in the art will appreciate that the tension bar(s) need not have the configuration shown in
Once tension bars 26 have been inserted, the stress established by the fixture is slightly relaxed by rotating crank 69 in the opposite direction. The tension blocks retract slightly toward each other until the tension bars 26 are fully seated in the tension blocks. Once the tension bars are properly seated in the tension blocks, further axial movement of the tension blocks toward each other is precluded. The tension bars are sized to maintain the tension blocks a sufficient distance apart, to thereby maintain the stress, or tension, on the blades. Thus, it will be appreciated that in the inventive blade assembly 10, the blades 30 serve to hold the system together, while the tension bars 26 prevent the blades from losing their tension.
When positioned in a food slicing device, such as slicer 50 shown in
Slicer 50 includes a push block 56 or similar mechanism to force the produce through the blade assembly. In the embodiment shown, push block 56 rides on guide rods 55. Push block 56 may be formed of any compatible material having the strength to push a food product through the blades of the blade assembly. Preferably, the push block is formed of a lightweight, low-friction and wear-resistant composition having sufficient strength and structural integrity to push the food product through the blades of the blade assembly. Those skilled in the art will appreciate that many suitable compositions may be utilized for such purposes. Non-limiting examples of such compositions include various plastics, such as acetal copolymers. DELRIN® and CELCON® are examples of particularly preferred plastics that may be utilized to form the push block.
Grippable handle 57 may be provided to allow for easy control of the push block as it is maneuvered up and down the guide rods. Preferably, elastomeric bumpers 58 are provided at the terminal end of the path of the guide rods. Bumpers 58 soften the impact of push block guide 59, and are sized to prevent the teeth 57 of push block 56 from directly engaging blades 20 during the downstroke of push block 56.
As stated, slicer 50 is merely one possible example of a slicing device upon which blade assembly 10 may be mounted. Those skilled in the art will appreciate that many other configurations are also suitable for use in conjunction with blade assembly 10.
As illustrated in
As illustrated in
Blade assembly 100 used in slicer 90 differs slightly from blade assembly 10, in that tension block hole 120 is preferably oriented generally parallel to hole 118, rather than perpendicular as in the previous designs. This arrangement facilitates the fixation of blade assembly 100 in slicer 90, as shown in
Frame 92 and bridge 93 are proportioned for good foundry practice. The arrangement shown permits easy installation of the blade assembly 100, as well as simple removal of the blade assembly for cleaning, repair, or replacement. In this embodiment, it is generally preferred to orient the blade assembly 100 at an angle of between about 30° and 45°, more preferably about 35°, to the axis in the direction the produce is pushed, thereby achieving a “shearing” action while slicing. An angle of 30° to 45° is common in machines of this type.
Slicer 90 also includes a pusher assembly 95 for pushing the produce through the blade assembly 100. Pusher assembly 95 is similar to the design of other existing machines currently in use. Preferably, pusher assembly 95 co-acts with a conventional movable portion, such as a slide board 96 having grooves 97 on the outer edges, to guide the pusher assembly as thrust is applied to push the tomato in an axial direction through the blade assembly 100. This action is consistent with existing devices.
The bridge 93 provides structural integrity to the slicer 90, and is designed to facilitate easy handling. Conventional guards 98 and 99 may be provided for operator safety. The pusher assembly 95 may be retained upon the slide board 96 by any suitable means, such as stop 101 and thumbscrews 102. This permits simple removal of the pusher assembly 95 for cleaning. A table stop 105 may be provided to retain the machine's position on the work surface while in use, and to hang it for storage when not in use.
Other features of slicer 90 that have not been described herein are conventional, and further explanation is not required for a full understanding of the present invention. In addition, many of the features described are conventional, and have been discussed only to provide general direction of the operation of slicer 90. Those skilled in the art will appreciate that slicer 90 is only one example of numerous possible designs that may be used with a horizontally-aligned set of blades according to the present invention, all of which are considered within the scope of the invention.
Those skilled in the art will appreciate that the components, such as the blades and the tension bars, can be made to any desired length, such that any desired level of stress may be established and maintained on the blades. Since the blade assemblies 10, 100, described herein are each unitized, they may each be easily handled as a separate entity. The simple manufacturing processes result in an economical component, and a candidate for “throw-away” replacement. However, if desired, the blade assembly can simply be recycled if the blades should become dull or damaged. In this event, the tension can be removed in the system by cutting the blades, thereby releasing the tension on the tension blocks, and allowing the blade assembly 10, 100 to come apart. Replacement blades 30, 130 can be installed in the same manner as the original blades, and suitable tension can be re-established in the blades as described previously. This action may conveniently occur pursuant to a manufacturer's “return-and-exchange” type program. In this manner, the customer simply returns the damaged or worn blade assembly, and is provided with a replacement assembly, fully tensioned and in condition for further use.
When utilizing a slicer having a unitized blade assembly 10, 100 as shown, the machine frame does not require extra strength considerations to accommodate the stresses of the initial tension of the blades. By using extruded aluminum components, the components can be made lighter than in comparable devices.
The present invention provides at least the following benefits when compared to prior art devices:
It is therefore intended that the foregoing detailed description be regarded as illustrative rather than limiting, and that it be understood that it is the following claims, including all equivalents, that are intended to define the spirit and scope of this invention.
The present patent document claims the benefit of the filing date under 35 U.S.C. §119(e) of Provisional U.S. Patent Application Ser. No. 60/645,058, filed Jan. 19, 2005, which is hereby incorporated by reference.
Number | Date | Country | |
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60645058 | Jan 2005 | US |