US20090314816A1

US20090314816A1 - Material Feed Device

Info

Publication number: US20090314816A1
Application number: US12/487,289
Authority: US
Inventors: Robert Schroeder; William E. O'Connor
Original assignee: Pacific Bearing Co
Current assignee: Pacific Bearing Co
Priority date: 2008-06-19
Filing date: 2009-06-18
Publication date: 2009-12-24

Abstract

A material feeder apparatus for feeding stock material to a machining device is provided. The material feeder apparatus includes a drive motor, a drive wheel, a guide wheel and a positioning mechanism. The drive wheel is operably coupled for rotation to the drive motor. The guide wheel is spaced apart from the at least one drive wheel defining a stock material slot therebetween. The positioning mechanism is to at least on of the drive wheel and the guide wheel for adjusting the stock material slot defined by the spacing between the at least one guide wheel and the at least one drive wheel. The material feeder apparatus may include both a drive and slave stock material feeder that are daisy chained together for being simultaneously driven by a single drive motor.

Description

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This patent application claims the benefit of U.S. Provisional Patent Application No. 61/074,077, filed Jun. 19, 2008, the disclosure and teachings of which are incorporated herein, in their entireties, by reference.

FIELD OF THE INVENTION

The present invention relates to methods and apparatus for feeding materials to a machining device. More particularly, the invention relates to methods and apparatus for feeding elongated pieces of stock material to a machining device.

BACKGROUND OF THE INVENTION

Raw stock material such as rod stock or bar stock-type material can be fed into machining devices to further machine the rod stock or bar stock to a particular shape. Feeding may be done manually or automatically. The present invention relates to improvements in the art of feeding material to a machining device.

BRIEF SUMMARY OF THE INVENTION

In one aspect, the invention provides a material feeder for feeding stock material to a machining device. The material feeder includes a drive motor, at least one drive wheel, at least one guide wheel and a positioning mechanism. The drive wheel is operably coupled for rotation to the drive motor. The at least one guide wheel is spaced apart from the at least one drive wheel defining a stock material slot therebetween. The positioning mechanism is operatively connected to at least one of the drive wheels and at least one of the guide wheels for adjusting the stock material slot defined by the spacing between the at least one guide wheel and the at least one drive wheel.
Other aspects, objectives and advantages of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention and, together with the description, serve to explain the principles of the invention. In the drawings:

FIG. 1 is a top perspective view of a first embodiment of a stock material feeder according to the teachings of the present invention;

FIG. 2 is a perspective exploded illustration of the material feeder of FIG. 1;

FIG. 3 is a side profile illustration of the stock material feeder of FIG. 1;

FIG. 4 is a top perspective illustration of an alternative embodiment of the stock material feeder incorporating a slave unit; and

FIG. 5 is a simplified schematic top view illustration of the system of FIG. 4.

While the invention will be described in connection with certain preferred embodiments, there is no intent to limit it to those embodiments. On the contrary, the intent is to cover all alternatives, modifications and equivalents as included within the spirit and scope of the invention as defined by the appended claims.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1-3 illustrate an embodiment of a stock material feeder 110 or apparatus for feeding stock material to a machining device. The configuration of the stock material feeder 110 allows the stock material feeder to feed stock material along a feed axis illustrated as double-headed arrow 112. As such, the stock material feeder can feed the material into or draw the material out of a machining device, such as a CNC milling machine or a threading machine or other similar machining device. However, the type of machine to which material is being fed is merely for illustrative purposes and to provide a sense of the environment in which the device will operate and is to not be limiting on the scope of the invention. The feeding provided by the stock material feeder can be automated.
The stock material feeder includes an electric motor 114 that operatively drives a plurality of drive wheels 118, 119 that engage an outer surface of the stock material to drive it along the feed axis 112. The drive wheels are preferable formed of a rubber material. The rubber material may have varying hardness values depending on the stock material being fed. For example, if the stock material being fed is a very raw material having surface impurities or defects, the rubber material of drive wheels 118 and 119 may be sufficiently hard to prevent damage thereto by the defects in the surface of the stock material. Alternatively, the rubber drive wheels 118, 119 may be relatively soft if the material being fed needs to maintain a clean surface appearance so as to prevent marring or damaging of the surface of the stock material. Further, the drive wheels 118, 119 may have a contoured outer surface that is contoured to the specific shape of the stock material being fed. For example, if the stock material being fed has a octagonal-shape, the guide wheels may have a three-sided surface such that three of the sides of the surface engage three corresponding sides of the raw stock material. Such contouring of the radially outer surface of the drive wheels 118, 119 further promotes receipt of the stock material by the drive wheels 118, 119.
With primary reference to FIG. 2, the drive wheels 118, 119 are coupled to the electric motor 114 by a plurality of gears 122-124. Gears 122, 123 are affixed to drive shafts 126, 128 while gear 124 is coupled to a coupling 130 that is connected to an output shaft 132 of the electric motor or output shaft of a gear train/transmission coupled to an output shaft of the electric motor 114. The drive gear 124 does not rotate relative to coupling 130 or drive shaft 132 such that rotation of the drive shaft 132 causes the drive gear 124 to similarly rotate. Additionally, drive gears 122, 123 are mounted to drive shafts 126, 128 such that drive gears 122, 123 do not rotate relative to drive shafts 126, 128.
Drive belt 134 couples drive gears 122, 123 to drive gear 124 such that driving of drive gear 124 causes the motor to also drive gears 122, 123. The drive wheels 118, 119 are similarly connected to drive shafts 126, 128, respectively, such that driving of the drive gears 122, 123 drives the drive wheels 118, 119 through the drive shafts 126, 128. It shall be understood that gears 122-124 all rotate in the same rotational direction via drive belt 134. Other gearing arrangements are contemplated to step up or step down drive rates.
The drive shafts 126, 128 also include gears 136, 138, respectively. Gears 136, 138 are coupled to drive shafts 126, 128 preferably through a slit or one way clutch that allows slippage therebetween in the event of binding. More particularly, gears 136,138 are used in combination with an additional drive belt or chain and the electric motor 114 to drive one or more adjacently positioned feed mechanisms, also known as “daisy chaining.”This is more fully described with regard to FIGS. 4 and 5 below. The adjacent feed mechanisms will have their similar gears 136, 138 coupled to the gears of the primary stock material feeder 110 by a belt or chain. As such, the electric motor of the primary stock material feeder 110 will drive the drive wheels of the additional material feeders as the two material feeders will be coupled by their gears 136, 138. The adjacent feed mechanisms that are daisy-chained to the illustrated stock material feeder 110 typically will not include a drive motor 114.
With reference to FIG. 1, the stock material feeder 110 also includes a slave unit 144, which also may be referred to as a guide unit. The slave unit 144 is spaced apart from the drive unit 111 forming a stock material feeding slot 146 therebetween through which the stock material is driven by drive wheels 118, 119 as it is fed to a machining device along axis 112.
Slave unit 144 includes a second set of wheels 148, 149. These wheels 148, 149 are guide wheels that freely rotate about axles 150, 151. The axles 150, 151 extend between top and bottom mounting plates 153, 155. The mounting plates 153, 155 are vertically separated by a pair of standoffs.
The stock material feed slot 146 is more particularly defined between drive wheels 118, 119 and guide wheels 148, 149. Stock material that is driven or fed by stock material feeder 110 is laterally pinched or engaged between the drive wheels 118, 119 and guide wheels 148, 149 in a direction extending generally perpendicular to feed axis 112. As such, as the drive wheels 118, 119 engage a side of the stock material and drive the stock material through stock material feed slot 146 along feed axis 112, the opposed side of the stock material engages and is guided by the guide wheels 148, 149 causing the guide wheels 148, 149 to rotate about axles 150, 151.
The drive unit 111 and the slave unit 144 are operably mounted to a positioning assembly 154 so as to position the two components relative to one another to adjust the width of the stock material feed slot 146. The positioning assembly includes a pair of carriages 156, 158 that are mounted for linear actuation along a guide rail 160 that is perpendicular to feed axis 112. The positioning assembly 154 further includes a drive shaft 162 that has a first half of right-handed threads and a second half of left-handed threads that interact with drive nuts 164, 165. As such, as the drive shaft is rotated about its axis of rotation by a user, particularly a user rotating handle 166, the nuts 164, 165 are either translated toward or away from one another depending on the direction of rotation of drive shaft 162. The drive nuts 164, 165 are coupled to the carriages 156, 158, and as a result, as the user rotates handle 166 the carriages 156, 158 will travel toward or away from each other at an equal velocity. As such, the material feed slot 146 width is variable, and will be centered at the midpoint of the length of the guide rail 160. Drive shaft 162 could optionally be coupled for an electronic motor or other actuator for automatic or programmed adjustment of the width of feed slot 146. The motor actuator would typically replace handle 166.
The carriages 156, 158 preferably include channels that interact with the guide rail 160. The carriages 156, 158 further preferably include Teflon or similar low friction material bearings 170, 171 to prevent or reduce friction between the carriages 156, 158 and the guide rail 160. The drive unit 111 and slave unit 144 preferably include part supports 174 that are positioned, at least in part, laterally inward from the drive wheels 118, 119 and the guide wheels 148, 149. These part supports 174, support the stock material as it is being fed by the stock material feeder 110. In a preferred embodiment, the part supports 174, 176 are or include a ceramic support pad having top surface portion upon which the stock material slides as it is being fed by the stock material feeder 110. The top surface being orthogonal to the axes of rotation for the drive and guide wheels 118, 119, 148, 149. The ceramic part support 174 reduces friction as well as reduces wear on the stock material as it is being fed by stock material feeder 110. The part supports 174, 176 have tapered ends to avoid catching ends of the stock material as it is fed through feed slot 146. Further, the part supports 174 are mounted onto support members. The support members, such as for slave unit 144, are attached to the bottom mounting plate 155. Further, the part supports 174 have a top surface that is proud of the top surface of the corresponding and adjacent bottom mounting plates 155.
Guide rail 160 includes a plurality of slots and holes 176 that can be used to mount the positioning assembly 154, and particularly the guide rail 160 to other structures. Guide rail 160 includes two rails for supporting the carriages 156, 158 to provide lateral support and prevent twisting.
In a preferred embodiment, guide rail 160 is sufficiently long enough such that stock material feed slot 146 can be at least 18 inches wide between the drive wheels 118, 119 and the guide wheels 148, 149. However, other configurations can be formed such that the stock material feed slot can have maximum widths that are larger than 18 inches or less than 18 inches. Further, in additional embodiments, as noted above, the handle 166 can be removed and replaced with a drive motor such that the positioning of the drive unit 111 relative to the slave unit 144 can be automatically positioned. Further, when using automatic positioning of the drive unit 111 relative to slave unit 144, other drive mechanisms such as opposed cylinders or lead or ball screws can be implemented.
Preferably, the stock material feeder includes a controller (not shown) that can be used to control the electric motor 114 at variable speeds. This allows the stock material feeder 110 to increase or decrease the feed rate at which the stock material is being fed to the machining device rather than driving the stock material from a single point.
This ability to vary the feed rate further promotes the added benefit of being able to daisy-chain a plurality of additional feed devices to the primary stock material feeder 110, such as through the use of gears 136, 138. More particularly, if it is desired to slow down or speed up the feed rate, all of this can be done simply by reducing or increasing the speed of drive motor 114. There is no need to coordinate the acceleration or deceleration of a plurality of drive motors. Further, the control of a plurality of motors to maintain a constant speed between the different feed devices is eliminated. Additionally, the ability to daisy-chain a plurality of feed devices allows the devices to be tailored to the length of the stock material that is being fed. More particularly, the longer the stock material additional feed devices can be added to more properly engage and drive the stock material toward the machining device.
It should also be noted, that the stock material feeder 110 can be used to draw material out of a machining device such that it is securely drawn from a machining device after it has been machined. As such, one stock material feeder can be positioned as an input feeder while a second stock material feeder 110 can be used as an output feeder.
When a stock material feeder 110 is used as an output feeder, the drive wheels 118, 119 and guide wheels 148, 149 can be contoured to the output shape of the material. Much like the wheels can be contoured to the corresponding shape of the material as it is being fed to the machining device.
FIG. 4 illustrates a further stock material feed apparatus 200 that incorporates a stock material feeder 110 from the previous embodiment and a second auxiliary stock material feeder 210 (also referred to as a slave stock material feeder or auxiliary feeder unit). As illustrated in FIG. 4, the auxiliary stock material feeder 210 is mechanically coupled to stock material feeder 110 by a chain. The chain couples gear 138 of stock material feeder 110 to gear 136 of auxiliary stock material feeder 210 such that the actuation provided by the drive motor 114 (not numbered in FIG. 4) is transferred to the auxiliary stock material feeder 210. More particularly, as the drive motor 114 operably drives drive wheels 118 and 119 as discussed above, the motor 114 will similarly drive gear 138. Driving of gear 138 will then result in driving of gear 136. As noted with regard to FIG. 1, the drive wheels 118, 119 of the auxiliary stock material feeder 210 are coupled by a drive belt such that driving of gear 136 will similarly drive both drive wheels 118 and 119 of the auxiliary stock material feeder 210.
With that being said, in the illustrated embodiment, the stock material feeder 110 and the auxiliary stock material feeder 210 are substantially identical except that the auxiliary material feeder 210 does not include its own drive motor, as it relies on drive motor 114 for its means of driving power. The coupling between the stock material feeder 110 and auxiliary stock material feeder 210 can be by way of chain, as illustrated, or alternatively by way of other coupling mechanisms such as a drive belt. The use of a chain or a drive belt allows for easy configuration of the material feed system by adjusting the lateral spacing between the various stock material feeders 110, 210 of the system depending on stock material length and need for intermediate stock material feeders.
While the embodiment only illustrates a single auxiliary stock material feeder 210, other embodiments can include a plurality of auxiliary material feeders 210. Further, the plurality of auxiliary material feeders may be on either side of stock material feeder 110. Further, a plurality of auxiliary material feeders 210 may be linked together without any intervening stock material feeders 110 including a drive motor 114.
With reference to FIG. 5, a simplified top-view illustration of the material feed system of FIG. 4 is illustrated. A piece of stock material, e.g. round rod stock, is being driven along feed axis 112 through stock material feed slots 146 of both the stock material feeder 110 and the auxiliary stock material feeder 210.
Due to the daisy chained arrangement, the stock material feeder 110 through drive wheels 118, 119 engages a first side of the piece of material 190 at a first location and drives the stock material 190 along the feed axis. The material feed system 200 also simultaneously engages the first side of the piece of material 190 at a second location, remote from the first location, and simultaneously drives the piece of material along the feed axis 112 at that second remote location. As used herein “remote location” shall refer to a location that is located at a separate stock material feeder (either a auxiliary or drive stock material feeder).
It should be noted that the material feed system 200 actually contacts the side of the stock material 190 at a plurality of points at a single location. More particularly, the individual stock material feeders 110, 210 each engage a single side of the stock material with drive wheels 118, 119. However, in view of the discussion of “remote location” above, these two different contact points by a single stock material feeder 110, 210 are not considered different locations, as used herein.
All references, including publications, patent applications, and patents cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.
The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) is to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

Claims

1. A material feeder apparatus comprising:

a drive motor;

at least one drive wheel operably mounted for rotation and operably coupled to the drive motor, such that the drive motor drives the at least one drive wheel;

at least one guide wheel spaced apart from the at least one drive wheel defining a stock material slot therebetween, the at least one drive wheel and at least one guide wheel having axes of rotation that are parallel; and

a positioning mechanism coupled to at least one of the drive wheels and at least one of the guide wheels for adjusting the spacing between the at least one guide wheel and the at least one drive wheel.

2. The material feeder apparatus of claim 1, wherein the positioning mechanism includes a guide rail and a pair of carriages mounted for linear motion about the guide rail, the drive motor and the at least one drive wheel forming a drive unit mounted to a first one of the carriages such that movement of the first one of the carriages also moves the drive motor, the at least one guide wheel forming a slave unit mounted to a second one of the carriages.

3. The material feeder apparatus of claim 2, wherein the positioning mechanism includes a drive shaft operably coupled to pair of carriages such that rotation of the drive shaft in a first direction causes the carriages to move away from one another along the guide rail and rotation of the drive shaft in a second direction, opposite the first direction, causes the carriages to move toward one another along the guide rail.

4. The material feeder apparatus of claim 2, further including an auxiliary feeder unit including an auxiliary drive unit and an auxiliary slave unit, the drive unit including a first coupling gear and the auxiliary drive unit including a second coupling gear, the first and second coupling gears operably coupled such that actuation of the drive unit by the drive motor simultaneously drives a drive wheel of the auxiliary drive unit and the drive wheel of the drive unit, the auxiliary drive unit being free of an independent source of power for driving the drive wheel of the auxiliary drive unit independent from the drive motor mounted to the drive unit.

5. The material feeder apparatus of claim 4, wherein the positioning mechanism includes a drive shaft operably coupled to pair of carriages such that rotation of the drive shaft in a first direction causes the carriages to move away from one another along the guide rail and rotation of the drive shaft in a second direction, opposite the first direction, causes the carriages to move toward one another along the guide rail.

6. The material feeder apparatus of claim 5, wherein the drive shaft includes a first portion that is right hand threaded and a second portion that is left hand threaded.

7. The material feeder apparatus of claim 6, further including support pads upon which material slides as it is being fed by the material feeder through the stock material slot, wherein at least one support pad is removably mounted to each of the carriages proximate a corresponding guide wheel or drive wheel, wherein the support pads are positioned, at least in part, laterally inward from the corresponding drive wheel or guide wheel, the top surface of the support pads being substantially perpendicular to the axes of rotation of the guide and drive wheels define a vertical support for the stock material slot.

8. The material feeder apparatus of claim 7, wherein the first and second coupling gears include slip clutches between the drive wheels permitting rotation of the coupling gears without requiring rotation of the drive wheels when a load greater than a predetermined amount opposes movement of one or more of the drive wheels.

9. The material feeder apparatus of claim 8, wherein the at least one drive wheel and the at least one guide wheel are formed from a rubber material, and the radially outer surfaces of the at least one guide wheel and at least one drive wheel are contoured.

10. The material feeder apparatus of claim 9, wherein the contours are concave V-shapes, wherein the V-shapes are truncated and include a flat bottom and two skewed sidewall extending from the flat bottom.

11. The material feeder apparatus of claim 2, further including support pads upon which material being fed by the material feeder slides as it is driven through the material feeder, top surfaces of the support pads defining a vertical support for the stock material slot, the top surfaces being orthogonal to the axes of rotation for the guide wheels and drive wheels.

12. The material feeder apparatus of claim 10, wherein at least one support pad is removably mounted to each of the carriages, wherein the support pads are positioned, at least in part, laterally inward from the corresponding drive wheel or guide wheel.

13. The material feeder apparatus of claim 4, wherein the first and second coupling gears include slip clutches between the drive wheels permitting rotation of the coupling gears without requiring rotation of the drive wheels when a load greater than a predetermined amount opposes movement of one or more of the drive wheels.

14. A method of feeding material to a machining device including the steps of:

engaging a first side of a piece of material at a first location with a first drive wheel and driving the material along a feed axis at that location with the first drive wheel;

simultaneously engaging the first side of the piece of material at a second location with a second drive wheel, remote from the first location, and simultaneously driving the piece of material along the feed axis at that second location with the second drive wheel;

laterally supporting the piece of material on an second side, opposite the first side, with a first guide wheel laterally spaced from the first drive wheel and forming material feed slot therebetween, the first guide wheel being positioned at the first location along the feed axis; and

simultaneously supporting the piece of material on the second side with a second guide wheel at the second location long the feed axis, the second guide wheel being laterally spaced from the second drive wheel a same distance as the first drive wheel and guide wheel are laterally spaced.

15. The method of claim 14 further comprising the step of simultaneously driving the first and second drive wheels with a single motor located proximate the first location.

16. The method of claim 15 further comprising adjusting the distance between the first guide wheel and first drive wheel to adjust the material feed slot by simultaneously moving a first pair of carriages supporting the first drive wheel and first guide wheel laterally relative to one another in a direction perpendicular to the feed axis; and further comprising adjusting the distance between the second guide wheel and second drive wheel to adjust the material feed slot by simultaneously moving a second pair of carriages supporting the second drive wheel and second guide wheel laterally relative to one another in a direction perpendicular to the feed axis.