Fold-over chute safety device

Information

  • Patent Grant
  • 6719118
  • Patent Number
    6,719,118
  • Date Filed
    Tuesday, September 24, 2002
    22 years ago
  • Date Issued
    Tuesday, April 13, 2004
    20 years ago
Abstract
The spacing device mounted to a two-section chute system prevents inadvertent contact between the two chute sections. The spacing device includes a mounting flange and a blocking member positionable between first and second pivotally attached chute sections of a concrete mixing truck. The first chute section comprises an annular flange that is configured to contact an arcuate edge of the second chute section. The mounting flange is connected to a second end of the first chute section and the blocking member is attached to the mounting flange. The blocking member comprises a contact surface that is configured to engage a portion of the arcuate edge of the second chute section when the spacing device is in a blocking position. In the blocking position, the spacing device holds the first and second chute sections in a partially open position to prevent unintended contact between the chute sections.
Description




BACKGROUND OF THE INVENTION




The present invention relates to a safety device for a foldable two-section chute system of a concrete mixing truck. In particular, the present invention relates to a blocking member positionable between adjacent ends of two chute sections when the chute system is transitioning from a folded position to an unfolded position.




Concrete mixing trucks are a common sight on the roads and at construction sites.

FIG. 1

depicts a typical concrete mixing truck


10


used to transport, mix, and pour concrete. The concrete mixing truck


10


comprises a rotatable drum


12


connected to the frame of the truck


10


. The rotatable drum


12


has an outlet


14


directed towards a two-section chute system


16


comprised of a first chute section


18


and a second chute section


20


. The first chute section


18


has a first end


22


and a second end


24


. The first end


22


of the first chute section


18


is pivotally connected to the concrete mixing truck


10


. The second end


24


of the first chute section


18


is connected to a hydraulic cylinder


26


that is attached to the frame of the truck


10


. The second chute section


20


has a first end


28


opposing the second end


24


of the first chute section


18


. The first chute section


18


and the second chute section


20


are attached by a pivotal connection


30


located at top edges


32


,


34


of chute sections


18


,


20


, respectively, adjacent to the second end


24


of the first chute section


18


and the first end


28


of the second chute section


20


.




The two chute sections


18


,


20


are traditionally capable of being in either a folded position or an unfolded position. During transport, the chute sections


18


,


20


are placed in the folded position with the second chute section


20


resting on top of the first chute section


18


as shown in FIG.


1


. When the concrete is ready for pouring, the second chute section


20


is rotated about the pivotal connection


30


until the second end


24


of the first chute section


18


and the first end


28


of the second chute section


20


make contact. The hydraulic cylinder


26


aligns the unfolded two-section chute system


16


with the desired location for pouring concrete. Concrete in the rotatable drum


12


is moved through the outlet


14


onto the chute system


16


.




One of the problems related to the two-section chute system of concrete mixing trucks occurs when the second chute section is in the process of unfolding. To move from the folded position to the unfolded position, the second chute section is initially manually rotated to an angle sufficient to allow the second chute section to continue rotating by gravity into the final unfolded position. The two-section chute system is in the final unfolded position when the opposing end of the second chute section abuts the opposing end of the first chute section and the second chute section is forced to stop its rotation. The weight of the second chute section, combined with the momentum of the second chute section from the gravitational rotation, can cause injury to a person working alongside a concrete mixing truck in the event the person has a body part located between the opposing edges of the two chute sections. If a person is unaware that the second chute section is being unfolded, the person may not be able to remove the body part from the contact area of the two chute sections in time to avoid injury. It is thus desirable to improve the safety of two-section chute systems.




BRIEF SUMMARY OF THE INVENTION




The spacing device of the present invention prevents unintended contact between two pivotally attached chute sections of a concrete mixing truck, where the first chute section comprises an annular flange adjacent to a second end of the first chute section and the second chute section comprises an arcuate edge configured to contact the annular flange of the first chute section. The spacing device comprises a mounting flange connected adjacent to the second end of the first chute section and a blocking member connected to the mounting flange. The blocking member comprises a contact surface that is spaced from the annular flange and positioned to contact a portion of the arcuate edge of the second chute section when the blocking member is in a blocking position.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view of a concrete mixing truck with a two-section chute system known in the art.





FIG. 2

is a perspective view of a two-section chute system in a folded position showing the spacing device of the present invention.





FIG. 3

is a side view of a two-section chute system in a partially open position showing the spacing device of the present invention.





FIG. 4

is an enlarged side view of a two-section chute system showing the spacing device of the present invention.





FIG. 5

is an enlarged perspective view of an end portion of a first chute section with the spacing device of the present invention in a blocking position.





FIG. 6

is an enlarged perspective view of opposing portions of the first and second chute sections with the spacing device of the present invention in a non-blocking position.





FIG. 7

is an enlarged perspective view of the front facing side of the spacing device of the present invention.





FIG. 8

is an enlarged perspective view of an end portion of the first chute section with a second embodiment of the spacing device of the present invention in a blocking position.











While the above-identified drawing figures set forth preferred embodiments of the invention, other embodiments are also contemplated, as noted in the discussion. In all cases, this disclosure presents the present invention by way of representation and not limitation. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art which fall within the scope and spirit of the principles of this invention. It should be specifically noted that the figures have not been drawn to scale, as it has been necessary to enlarge certain portions for clarity.




DETAILED DESCRIPTION




To better illustrate the spacing device


36


of the present invention,

FIG. 2

is an enlarged perspective view of the two-section chute system


16


shown in FIG.


1


. The first chute section


18


is comprised of an elongated arcuate wall


38


that terminates in an arcuate edge


40


at second end


24


. The arcuate wall


38


of the first chute section


18


has a diameter D


1


at the second end


24


adjacent to the pivotal connection


30


. An annular flange


42


is connected to an outer surface


44


of the arcuate wall


38


adjacent to the arcuate edge


40


of the first chute section


18


. The second chute section


20


is comprised of an elongated arcuate wall


46


that terminates in an annular, arcuate edge


48


at the first end


28


. The arcuate wall


46


of the second chute section


20


has a diameter D


2


at the first end


28


adjacent to the pivotal connection


30


. The diameter D


2


of the second chute section


20


is slightly greater than the diameter D


1


of the first chute section


18


.




The pivotal connection


30


is formed by a hinge


50


that connects the top edge


32


of the first chute section


18


to the top edge


34


of the second chute section


20


near the arcuate edges


40


,


48


. In the transition from the folded position to the unfolded position, the second chute section


20


is rotated about the hinge


50


. Because the diameter D


2


of the arcuate wall


46


of the second chute section


20


is greater than the diameter D


1


of the arcuate wall


38


of the first chute section


18


, an inner surface portion


52


of the second chute section


20


overlaps the outer surface portion


44


of the first chute section


18


when the chute sections


18


,


20


are in a fully unfolded position. In the unfolded position, arcuate edge


48


of the second chute section


20


engages annular flange


42


of the first chute section


18


.




To prevent the arcuate edge


48


of the second chute section


20


from uncontrollably coming into contact with the annular flange


42


of the first chute section


18


during the unfolding process, a spacing device


36


is connected to the chute system


16


. In one embodiment, the spacing device


36


is mounted to the annular flange


42


of the first chute section


18


near the hinge


50


. The spacing device


36


is comprised of a blocking member


54


with a contact surface


56


that is spaced rearwardly from the annular flange


42


of the first chute section


18


. The contact surface


56


of the blocking member


54


is positioned to make contact with a portion of the arcuate edge


48


of the second chute section


20


when the spacing device


36


is in a blocking position. The chute sections


18


,


20


, hinge


50


, and spacing device


36


each are formed from a heavy metal material.





FIGS. 3 and 4

are side views of the spacing device


36


in the blocking position. As shown in

FIG. 3

, spacing device


36


is located on first chute section


18


so as to prevent second chute section


20


from fully unfolding. Thus, spacing device


36


engages arcuate edge


48


of second chute section


20


at a point spaced from annular flange


42


. As shown in greater detail in

FIG. 4

, the spacing device


36


is positioned between the annular flange


42


of the first chute section


18


and the arcuate edge


48


of the second chute section


20


. As the second chute section


20


unfolds about the hinge


50


, the contact surface


56


of blocking member


54


is axially aligned with a portion of the arcuate edge


48


of the second chute section


20


, preventing engagement between the arcuate edge


48


of the second chute section


20


and the annular flange


42


of the first chute section


18


. The angle formed by the spacing device


36


while in the blocking position is a function of the angle of the contact surface


56


and is selected to create a gap G of sufficient size to prevent harmful contact of second chute section


20


against a person's extremities.




Spacing device


36


is urged towards the blocking position by a biasing means, which in one embodiment comprises an elongated coil spring


58


. Other biasing structures can be used without departing from the intended scope of the invention, as will be evident to those skilled in the art. The elongated coil spring


58


has a first end


60


and a second end


62


. The first end


60


of the coil spring


58


is connected to the second end


24


of the first chute section


18


. The second end


62


of the coil spring


58


is connected to the blocking member


54


. By way of a non-limiting example, the first and second ends


60


,


62


of the coil spring


58


are connected to the second end


24


of the first chute section


18


and the blocking member


54


, respectively, by eye-bolts


64


,


66


.





FIG. 5

is an enlarged perspective view of a portion of the second end


24


of the first chute section


18


with blocking member


54


in the blocking position. In one preferred embodiment, the blocking member


54


comprises first and second plates


68


,


70


. The first plate


68


has a first end


72


and a second end


74


, and a first edge


76


and a second edge


78


. The first plate


68


is pivotally attached to a mounting flange


80


by a pivotal connection


82


. A handle


84


is connected to the first edge


76


of the first plate


68


. The handle


84


extends in the same plane as the first plate


68


and away from the arcuate wall


38


of the first chute section


18


. A protrusion


86


is connected to the second edge


78


of the first plate


68


at second end


74


. The protrusion


86


extends in the same plane as the first plate


68


and towards the arcuate wall


38


of the first chute section


18


.




The phantom illustration of

FIG. 5

shows the inner sidelong portion of blocking member


54


. The protrusion


86


of the first plate


68


contacts the arcuate wall


38


of the first chute section


18


and helps align the contact surface


56


of the blocking member


54


with the arcuate edge


48


of the second chute section


20


when the spacing device


36


is in the blocking position. When in the blocking position, protrusion


86


is positioned to engage the outer surface


44


of the arcuate wall


38


of the first chute section


18


, adjacent to the annular flange


42


. Although

FIG. 5

depicts the protrusion


86


at the second end


74


of the second edge


78


of the first plate


68


, the protrusion


86


can be located at other areas along the second edge


78


of the first plate


68


without departing from the intended scope of the invention, as will be evident to those skilled in the art. The length of protrusion


86


is designed to space the blocking member


54


at a distance from the arcuate wall


38


of the first chute section


18


such that the contact surface


56


of the blocking member


54


is axially aligned with the arcuate edge


48


of the second chute section


20


. Thus, when the second chute section


20


is unfolding, the arcuate edge


48


of the second chute section


20


will engage the contact surface


56


of the blocking member


54


, preventing unintentional abutment of the first and second chute sections


18


,


20


.




The second plate


70


has a first end


88


and a second end


90


, and a first edge


92


and a second edge


94


. The first edge


92


of the second plate


70


is connected transversely to the first plate


68


, such as by welding, adjacent to the second edge


78


of the first plate


68


, forming a right angle between the first plate


68


and the second plate


70


. The second edge


94


of the second plate


70


comprises the angled contact surface


56


of the blocking member


54


. Both first and second plates


68


,


70


are formed from a metal, such as ASTM A


36


plate steel having a wall thickness of about 0.375 inches. In one preferred embodiment blocking member


54


has a height of about 4.50 inches, with contact surface


56


sloping at an angle of about 20 degrees relative to first plate


68


. For this preferred embodiment, the maximum width of second plate


70


relative to first plate


68


is about 2.50 inches.




The pivotal connection


82


connects the blocking member


54


to the mounting flange


80


. Although

FIG. 5

depicts the pivotal connection


82


of the blocking member


54


to the mounting flange


80


at the first end


72


of the first plate


68


, the pivotal connection


82


can be located at other areas of the first plate


68


without departing from the intended scope of the invention, as will be evident to those skilled in the art. The pivotal connection


82


allows the blocking member


54


to shift between the blocking and non-blocking positions. By way of a non-limiting example, the pivotal connection


82


of the blocking member


54


to the mounting flange


80


is formed by a nut and bolt connection


96


.




While the blocking member


54


of the present invention is comprised of first and second plates


68


,


70


, there are other forms that the blocking member


54


can take without departing from the intended scope of the invention, as will be evident to those skilled in the art. By way of a non-limiting example, the blocking member


54


may be comprised of a solid block of material with the pivotal connection


82


of the blocking member


54


to the mounting flange


80


located at an aperture extending through the entire length of the block. Alternatively, the blocking member


54


may be comprised of a solid block of material with the pivotal connection of the blocking member


54


to the mounting flange


80


located at a mortise section of the blocking member


54


.





FIG. 6

is an enlarged perspective view of blocking member


54


that has been pivoted out of the blocking position. The mounting flange


80


of spacing device


36


connects the blocking member


54


to the first chute section


18


. The mounting flange


80


is connected to the first chute section


18


adjacent to the arcuate edge


40


of the first chute section


18


and near the top edge


32


of the first chute section


18


. In one preferred embodiment, the mounting flange


80


is connected to the annular flange


42


of the first chute section


18


proximate to the top edge


32


of the first chute section


18


. The mounting flange


80


is formed from a metal, such as plate steel, like first and second plates


68


,


70


.




Blocking member


54


is pivoted from the blocking position to the non-blocking position by pulling on the handle


84


to pivot blocking member


54


until the contact surface


56


no longer engages the arcuate edge


48


of the second chute section


20


. As a result, the inner surface portion


52


of the arcuate wall


46


of the second chute section


20


is allowed to overlap the outer surface


44


of the arcuate wall


38


of the first chute section


18


, allowing the arcuate edge


48


of the second chute section


20


to engage the annular flange


42


of the first chute section


18


.





FIG. 7

is an enlarged perspective view of the front facing side of spacing device


36


in a non-blocking position. When it is confirmed that no body extremities are located between the first and second chute sections


18


,


20


, the blocking member


54


is pivoted away from the arcuate wall


38


of the first chute section


18


about the nut and bolt connection


96


. As the blocking member


54


is pivoted away from the first chute section


18


, the elongated coil spring


58


is stressed. With the spacing device


36


in the non-blocking position, the second chute section


20


completes the gravitational rotation about the hinge


50


and the arcuate edge


48


of the second chute section


20


engages the annular flange


42


of the first chute section


18


. When the two-section chute system


16


is in the fully unfolded position, the protrusion


86


of the first plate


68


rests against the first end


28


of the second chute section


20


. When the second chute section


20


is rotated back about hinge


50


to the folded position, blocking member


54


is urged back to the blocking position by elongated coil spring


58


.




The pivotal connection


82


of the blocking member


54


to the annular flange


42


offers an easy and reliable operation of spacing device


36


. In the event concrete slurry contacts the pivotal connection


82


, it is still able to reliably align blocking member


54


with the arcuate edge


48


of the second chute section


20


. The constant pivoting motion of the blocking member


54


between the non-blocking and blocking positions loosens and clears concrete fines or other foreign matter contacting spacing device


36


. Protrusion


86


provides a visual means for confirming that blocking member


54


has been fully returned to the blocking position and that it is ready for spacing the chute sections


18


,


20


in a subsequent unfolding process.





FIG. 8

is an enlarged perspective view of a portion of the second end


24


of the first chute section


18


with blocking member


54


in the blocking position. The first and second plates


68


,


70


, pivotal connection


82


and protrusion


86


of

FIG. 8

are identical to the first and second plates


68


,


70


, pivotal connection


82


and protrusion


86


described in FIG.


5


. According to the embodiment of

FIG. 8

, a weighted arm


98


replaces handle


84


and elongated coil spring


58


of the embodiment of FIG.


5


. The weighted arm


98


has a first end


100


and a second end


102


. The first end


100


of weighted arm


98


is connected to a lower corner


101


at the second end


74


of the first plate


68


. The weighted arm


98


extends at a predetermined angle in the same plane as the first plate


68


and away from the arcuate wall


38


of the first chute section


18


. The weighted arm


98


extends at an angle greater than 90 degrees and less than 180 degrees from the first edge


76


of the first plate. In one preferred embodiment, weighted arm extends at an angle of about 135 degrees relative to the first edge


76


of the first plate


68


.




The second end


102


of weighted arm


98


is bulbous and comprises a sufficient weight to return the blocking member


54


to the blocking position by gravity. In a preferred embodiment, the weighted arm


98


is 5.00 inches in length and has a weight of about 0.90 pounds with a center of gravity about 3.50 inches from the point of attachment of the first end


100


to the blocking member


54


. Arm


98


is made of a metal material.




The weighted arm


98


of blocking member


54


offers a simple and reliable means of urging the blocking member


54


to the blocking position. In the event concrete slurry contacts the spacing device


36


, the weighted arm


98


is still able to reliably align blocking member


54


with the arcuate edge


48


of the second chute section


20


. The weighted arm


98


relies on gravity alone to pivot the blocking member


54


about the pivotal connection


82


of the blocking member


54


to the mounting flange


80


back to the blocking position. As previously mentioned in

FIG. 7

, the constant pivoting motion of the blocking member


54


between the non-blocking and blocking positions loosens and clears concrete fines or other foreign matter from contacting spacing device


36


. The spacing device


36


of

FIG. 8

does not rely on any other movable members to return the blocking member


54


to the blocking position. After the blocking member


54


has been pivoted about pivotal connection


82


, protrusion


86


provides a visual means for confirming that blocking member


54


has been fully returned to the blocking position.




A spacing device of the present invention includes a blocking member that is pivotally attached to a flange mounted adjacent to an end of a first chute section. The blocking member provides a contact surface that engages an arcuate edge of a second pivotally attached chute section when the blocking member is in a blocking position and the second chute section is being unfolded. The contact surface of the blocking member spaces the opposing ends of the chute sections at a predetermined angle, preventing unintentional or uncontrolled contact between the first and second chute sections. When it is confirmed that it is safe to allow the arcuate edge of the second chute section to fully engage the first chute section, the blocking member is pivoted from the blocking position, thereby allowing the second chute section to complete the unfolding process.




Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.



Claims
  • 1. A concrete chute safety system having first and second chute sections of a concrete mixing truck, wherein the first chute section comprises an annular flange adjacent to a second end of the first chute section, and the second chute section comprises an arcuate edge configured to contact the annular flange of the first chute section, the second chute section being pivotally connected to the first chute section, the safety system comprising:a mounting flange connected to the first chute section adjacent to the second end and proximate to the pivotal connection of the first and second chute sections; a blocking member attached to the mounting flange, the blocking member comprising a contact surface spaced from the annular flange, the contact surface being positioned to contact a portion of the arcuate edge when the blocking member is in a first position.
  • 2. The safety system of claim 1 wherein the mounting flange is connected to the annular flange.
  • 3. The safety system of claim 1 wherein the mounting flange is connected to the first chute section adjacent the annular flange.
  • 4. The safety system of claim 1 wherein the mounting flange is welded to the first chute section.
  • 5. The safety system of claim 1 wherein the blocking member is pivotally attached to the mounting flange.
  • 6. The safety system of claim 5 and further comprising means for urging the blocking member towards the first position.
  • 7. The safety system of claim 6 wherein the means for urging the blocking member toward the first position comprises a spring having first and second ends, the first end connected to the first chute section, the second end connected to the blocking member.
  • 8. The safety system of claim 6 wherein the means for urging the blocking member toward the first position comprises a weighted arm extending from the blocking member.
  • 9. The safety system of claim 1 and further comprising a means for aligning the contact surface with the portion of the arcuate edge when the blocking member is in a first position.
  • 10. The safety system of claim 9 wherein the means for aligning the contact surface comprises a protrusion connected to the blocking member, the protrusion being positioned to contact the first chute section adjacent to the annular flange when the blocking member is in the first position and to align the contact surface with the arcuate edge of the second chute section when the blocking member is in the first position.
  • 11. The safety system of claim 1 wherein the contact surface of the blocking member is configured to retain the second chute section relative to the first chute section by a predetermined angle when the blocking member is in the first position.
  • 12. The safety system of claim 1 wherein the blocking member comprises:a first plate having first and second ends and first and second edges, the first plate attached to the mounting flange adjacent to the first end of the first plate; a second plate having first and second ends and first and second edges, the first edge of the second plate connected to the second edge of the first plate, the second plate extending generally transversely from the first plate, wherein the second edge of the second plate comprises the contact surface.
  • 13. The safety system of claim 12 wherein the first plate is pivotally attached to the mounting flange.
  • 14. The safety system of claim 1 and further comprising:a handle connected to the blocking member and spaced from the contact surface.
  • 15. A spacing device for use between first and second chute sections of a concrete mixing truck, wherein the first chute section comprises an annular flange adjacent to a second end of the first chute section, and the second chute section comprises an arcuate edge configured to contact the annular flange of the first chute section, the second chute section being pivotally connected to the first chute section, the spacing device comprising:a mounting flange for mounting to the first chute section adjacent to the second end and proximate to the pivotal connection of the first and second chute sections; a blocking member connected to the mounting flange, the blocking member comprising a contact surface spaced from the mounting flange, the contact surface being configured to contact a portion of the arcuate edge when the mounting flange is mounted to the first chute section, to maintain the first and second chute sections in a spaced relationship.
  • 16. The spacing device of claim 15 wherein the blocking member is pivotally connected to the mounting flange.
  • 17. The spacing device of claim 15 wherein the contact surface of the blocking member is configurable to retain the second chute section relative to the first chute section by a predetermined angle when the mounting flange is mounted to the first chute section and the blocking member is in a first position.
  • 18. The spacing device of claim 15 wherein the blocking member further comprises:a first plate having first and second ends and first and second edges, the first plate attached to the mounting flange adjacent to the first end of the first plate; a second plate connected to the second edge of the first plate, the second plate extending transversely from the first plate, wherein the second edge of the second plate comprises the contact surface.
  • 19. The spacing device of claim 18 wherein the first plate is pivotally attached to the mounting flange.
  • 20. The spacing device of claim 16 and further comprising means for urging the blocking member toward a first position when the mounting flange is mounted to the first chute section.
  • 21. The spacing device of claim 20 wherein the means for urging the blocking member toward the first position comprises a spring having first and second ends, the first end connectable to the first chute section, the second end connected to the blocking member.
  • 22. The spacing device of claim 20 wherein the means for urging the blocking member toward the first position comprises a weighted arm extending from the blocking member.
  • 23. The spacing device of claim 15 and further comprising:a handle connected to the blocking member and spaced from the contact surface.
  • 24. The spacing device of claim 15 further comprising a means for aligning the contact surface with the portion of the arcuate edge when the mounting flange is mounted to the first chute section and the blocking member is in a first position.
  • 25. The spacing device of claim 24 wherein the means for aligning the contact surface comprises a protrusion connected to the blocking member, the protrusion being positionable to contact the first chute section adjacent to the annular flange and to align the contact surface with the arcuate edge of the second chute section when the mounting flange is mounted to the first chute section and the blocking member is in a first position.
  • 26. A blocking device for use with a concrete chute safety system on a concrete mixing truck wherein the concrete chute includes a first chute section having a first end connected to the truck, the first chute section having an annular flange adjacent to a second end of the first chute section and having a mounting flange adjacent to the annular flange, the concrete chute further including a second chute section having an arcuate edge configured to contact the annular flange of the first chute section, the second chute section being pivotally attached to the first chute section adjacent to the arcuate edge and the second end of the first chute section, the blocking device comprising:a blocking member, the blocking member comprising a first surface configured for connection to the mounting flange, and a second surface, spaced from the first surface, the second surface configured to contact the arcuate edge of the second chute section when the blocking member is mounted to the mounting flange.
  • 27. The blocking device of claim 26 wherein the blocking member is pivotally mountable to the mounting flange.
  • 28. The blocking device of claim 26 wherein the second surface of the blocking member is configured to retain the second chute section relative to the first chute section by a predetermined angle when the blocking member is mounted to the mounting flange and in a first position.
  • 29. The blocking device of claim 26 and further comprising:a first plate having first and second ends and first and second edges, the first plate attached to the mounting flange adjacent to the first end of the first plate, wherein the first plate comprises the first surface of the blocking device; a second plate connected to the second edge of the first plate, the second plate extending transversely from the first plate, wherein the second edge of the second plate comprises the second surface of the blocking member.
  • 30. The blocking device of claim 29 wherein the first plate is pivotally attachable to the mounting flange.
  • 31. The blocking device of claim 29 and further comprising:a handle connected to the first edge of the first plate.
  • 32. The blocking device of claim 31 wherein the handle comprises a weighted arm.
US Referenced Citations (8)
Number Name Date Kind
1946222 Mandt Feb 1934 A
2488292 Hilkemeier Nov 1949 A
3053367 Lynch Sep 1962 A
3456769 Prichard et al. Jul 1969 A
3542179 Prichard Nov 1970 A
4498568 Christenson Feb 1985 A
4919249 Alexander Apr 1990 A
5660260 Bareiss Aug 1997 A
Foreign Referenced Citations (1)
Number Date Country
731010 Jun 1955 GB
Non-Patent Literature Citations (1)
Entry
Schwing America drawings (6 sheets) of device on sale in the U.S. prior to Aug. 24, 2001.