Pocket assembly for placing a flat dowel between cast in place concrete slabs
An assembly for use in the formation of adjacent concrete slabs to provide a flat rectangular dowel engaged between the slabs. The assembly comprises a pocket which is cast in place in the edge portion of the first slab to be formed, with the dowel fully confined within the pocket. After the formation of the first slab, the dowel is partially withdraw from the pocket and the second slab is formed in place against the first slab, with the dowel in spanning relationship to the respective slabs. In the preferred embodiments, the pocket comprises a monolithic plastic box having complimental generally rigid upper and lower sections movable between a closed condition defining the pocket therebetween and an open condition exposing the pocket interiorly. One edge of the pocket is formed with an opening through which the dowel passes as it moves between the fully confined and the partially withdrawn positions. In certain embodiments, a sealing element or door is provided to close the opening during the formation of the first slab. Seal elements are also provided to seal the pocket against the intrusion of concrete during the formation-of the second slab.
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This application is based upon and claims the benefit of Provisional Application 60/787,125, filed Mar. 29, 2006.
BACKGROUND OF THE INVENTIONThe present invention relates to an assembly for use in the formation of adjacent concrete slabs to provide an embedded flat planar dowel to maintain the slabs in generally horizontal alignment, while permitting limited lateral movement of the slabs relative to one another. In its more specific aspects, the invention is concerned with such an assembly which provides a pocket cast in place within the first slab to be formed and a dowel within the pocket which may be partially withdrawn for embedment within the second slab to be formed.
The provision of dowels to transfer loads between adjacent cast in place concrete slabs is well known. Generally these dowels are a conventional cylindrical configuration. It is also known to provide dowels for this purpose which are of a flat diamond-shape, as may be seen from U.S. Pat. No. 6,354,760. The flat configuration has the advantage that it increases the bearing area of the dowel.
The prior art also teaches the provision of load transferring dowels for adjacent concrete slabs where some type of resilient spacer is provided around part of all of the dowel to accommodate limited movement between the slabs and the dowel. Such arrangements are seen, for example, in U.S. Pat. Nos. 6,354,760; 6,145,262, 5,674,028; 5,040,350; and 4,733,513. In some instances, these spacers comprise a sheath which is cast in place in the edge of a slab, with the dowel in place in the sheath and extending therefrom. The later arrangement may be seen in U.S. Pat. No. 6,354,760.
A disadvantage of the prior art spacers and sheaths is that either the dowel, or some type of a mounting plate is disposed within and extends from the dowel or sheath during its placement within the slab being formed. This requires that the form be configured to accommodate the plate or dowel and also risks that cement may intrude around the dowel and the spacer, during the formation of the concrete slab. Also, in the case where a mounting plate is used, the plate is yet another piece of apparatus which needs to be provided and, ultimately, removed.
SUMMARY OF THE INVENTIONThe present invention provides an apparatus and method for positioning a load transferring dowel between adjacent cast in place concrete slabs. The apparatus comprises a pocket forming member having a dowel received therein for movement between a first position fully confined within the pocket of the member and a second position extending partially out of an opening in the pocket. A fastener is provided for securing the member to a form, with the opening in juxtaposition to the form and the dowel fully confined within the pocket. In this basic combination, the form serves to close the opening in the pocket. Additionally, a door or sealing element may be provided to close the pocket, prior to its attachment to the form.
The method comprises first providing a pocket forming member having a pocket therein slidably receiving a dowel for movement between a first position confined within the pocket and a second position extending through an opening formed in one end of the pocket. The remaining method steps comprise:
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- 1. securing the pocket forming member to an edge forming member of a form, with the dowel in the first position;
- 2. forming concrete against the forming member to provide a first concrete slab having the pocket forming member embedded therein, with the opening disposed at one edge of the slab;
- 3. removing the forming member to expose the opening;
- 4. pulling the dowel partially of the pocket; and
- 5. forming concrete against the edge of the first concrete slab to provide a second slab having the portion of the dowel embedded therein.
A principal object of the invention is to provide an assembly which may be used to both form a pocket in the edge of a cast in place concrete slab and provide a dowel which may be partially withdrawn from the pocket and cast in place within an adjacent concrete slab.
Another object of the invention is to provide such an assembly wherein the dowel is of a generally planar configuration, over the length thereof spanning the cast in place slabs.
Still another object of the invention is to provide such an assembly wherein the dowel is laterally confined between resilient members to accommodate relative lateral movement of the slabs.
Still another object of the invention is to provide such an assembly wherein stop or detent elements are provided to enable the dowel to be adjusted to a select position of extension relative to the pocket forming member.
A further object of the invention is to provide such an assembly wherein seals are provided to prevent the intrusion of fluid concrete into the pocket forming member during the formation of a concrete slab.
Yet another object of the invention is to provide such an assembly wherein the pocket in the pocket forming member is fully sealed during the formation of the first to be formed slab.
These and other objects will become more apparent when viewed in light of the accompanying drawings and following detailed description.
This embodiment, as seen in
The pocket forming member P1 is of a monolithic construction and comprises upper and lower sections 10 and 12 with an integral hinge 14 therebetween. The sections 10 and 12 are of a generally trough-shaped cross-section and are formed with inwardly extending protrusions, in the form ribs 16 extending longitudinally thereof. Side walls 18 are formed on the upper section 10 and side walls 20 are formed on the lower section 12. Fastening ears or flanges 22 are formed on and extend outwardly from the sections 10 and 12. Mutually engagable latch elements 24 and 26 are also formed on the upper and lower sections. The latch elements 24 extend outwardly from the walls 18 and are of generally hooked shaped configuration, as may be seen from
The dowel D1 of a rectangular configuration, as viewed in plan, generally complimental to the interior of the pocket forming member. It is movable between a first position fully confined within the pocket forming member (see
The ribs 16 limit contact of the dowel D1 with the interior of the pocket forming member. This, together with the disposition of the ribs in a direction extending parallel to the direction of movement of the dowel (the arrow lines in
The pocket forming member of this embodiment is illustrated in
The pocket forming member P2 is similar to the member P1 in that it comprises upper and lower sections 40 and 42, respectively, hingedly secured together by an integrally formed hinge 44. The upper section is formed with side walls 48 and the lower section is formed with side walls 50. The fastener member of the second embodiment comprises flanges 52 and 54 which provide a collar extending around at the open end of the member P2. These flanges have open ended slots 56, 58, 60 and 62 extending therethrough for the receipt of nail or screw fasteners used to secure the pocket forming member to the edge forming member of the form. The door 36 is integrally formed with the pocket forming member P2 and is joined to the flange 54 by an integral hinge 64. Openings 66 extend through the door 36 for alignment with the open ended slots in the flanges 52 and 54 and cutout portions at the lateral edges of the flanges. The cutout portions are seen in
Latch elements 70, 72, corresponding to the elements 24, 26 of the pocket forming member P1 are secured to the exterior of the pocket forming member P2. Interiorally, the pocket forming member P2 has integrally formed resilient detent members 74, 76. These members are disposed to engage grooves 78, 80 and 82 in the lateral edges of a dowel D2 received within the pocket forming member P2 (see
As shown in
The dowel D2 is manufactured of a metallic material, such as steel. In plan view, it is of a rectangular configuration generally complimental to that of the pocket formed within the pocket forming member P2. Typical dimensions for the dowel D2 are 3 inches deep, by 5 inches wide, by ⅜ inch thick, with a clearance of ¼ inch between the side edges of the dowel and the interior of the pocket. The forward edge of the dowel is formed with a trapezoidal cutout 88 for receipt of a complimental finger grip insert 90. The insert may be formed of any suitable material, such as injected molded polymer. Its cross-section is shown in
The pocket forming member of this embodiment is identified, in its entirety, by the reference letter P3. The member P3 is injected molded from the same type of polymer described with reference to the pocket forming members P1 and P2 of the first and second embodiments. It comprises an upper section 100 and a lower section 102 disposed for movement toward one another, as depicted in
The sections 100 and 102 differ from the sections 40 and 42 of the second embodiment in that the upper section 100 is of a shallower depth than the upper section 40 and in that the sections are not hingedly joined. Rather, they are provided with four sets of paired latch elements 70, 72. These elements snap into engagement, to secure the sections 100 and 102 together, as seen in
The dowel D4 is of a thinner construction then the dowels D1, D2 and D3 and also differs in construction from these dowels in that it is so proportioned that spaces 108 and 110 are provided to the sides and rear of the dowel, when it is received within the pocket member P3 (see
The lower section 102 of is formed with spring leaves 130 and 132 (see
In use, the third embodiment pocket assembly and dowel is placed in first and second formed concrete slabs in a manner identical to that of the pocket forming member P2 and dowel D2 of the second embodiment. In the resulting concrete structure, the only difference being that the dowel is of a thinner configuration and that the leaves and detent members operate somewhat differently, as described above.
The different depths of the upper and lower sections 100 and 102, and the absence of a hinged connection therebetween, enable two sections corresponding generally to the section 100 to be mated together to accommodate a thinner dowel, or that two thick sections, such as the section 106, to be mated together to accommodate an thicker dowel. This adds to the versatility of the third embodiment, without the necessity of providing special molds for the manufacture of different upper and lower sections. To accommodate such a combination of two thin or two thick sections, the latch elements 70, 72 would be constructed so that they could snap together, irrespectively of the combination in which the sections were assembled.
DESCRIPTION OF THE THIRD EMBODIMENTThe pocket forming member of this embodiment is identified by the reference letter P4. The member P4 is injection molded from the same type of polymer described with reference to the pocket forming members P1, P2 and P3. It is similar to the pocket member P1 in that it comprises upper and lower sections 132 and 134, respectively, hingedly secured together by an integrally formed hinge 136. The upper section is formed with sidewalls 138 and the lower section is formed with sidewalls 140. An end wall 142 extends between the sidewalls 138 and an end wall 144 extends between the sidewalls 140.
The fastener member of the fourth embodiment comprises flanges 146 and 148 which provide a collar extending around the open end of the member P4. These flanges have integrally formed complimental U-shaped fasteners 150, 152 formed on the interior surfaces thereof (see
The dowel of the fourth embodiment, designated D5, may be fabricated of metal or a polymer material similar to that described with reference to the dowel D1. It also has similar dimensions to the dowel D1 and is of a plan configuration complimental to that of the pocket in the pocket forming member P4, with space provided for between the dowel and the interior sidewalls of the pocket to accommodate limited lateral movement of the dowel relative to the pocket. Resilient spacers 161 are formed integrally with the section 134 to, at least initially, maintain the dowel D5 in alignment with the member P4. A tongue 162 is integrally formed with the dowel D5. When the dowel is retracted into the pocket member P4, the tongue 162 is fully confined within the member (see
The dowel D5 has an aperture 164 extending therethrough for receipt of an expansible spring pin 166. Grooves 170, 172 are formed in the upper and lower sections 132, 134, respectively, in alignment with the aperture 164 for slidable receipt with the ends of the pin 166. The grooves have integrally formed detent ramps 174, 176 for engagement by the ends of the spring pin 166. Ramps 176 are tapered on their forward and trailing edges to enable the pin to slide thereover in either direction. The ramps 174 are tapered on the side thereof facing to the interior of the pocket and are formed with abrupt edges 178 on the sides thereof facing the open end of the pocket member P4. As a result of this construction, the pin 166 may ride over the ramps as the dowel D5 is pulled out of the pocket forming member P4 from the retracted (first) position. When the pin reaches a position to the outside of the ramp 174, it snaps into place in the recess between the edges 178 and an end wall 179, as seen in
The manner of assembling the fourth embodiment may be seen from
The final step of conditioning the fourth embodiment for use is shown in
Tapered edges 183 on the flanges 146, 148 engage the sides of the dowel D5 (see
In use, the member P4 is fastened to an edge forming member 32, as seen in
As shown the rearward end dowel D5 is shown formed with a cutout of the same shape as tongue 162. This cutout performs no function. It is the result of a stamping process wherein successive dowels D5 are stamped from a common sheet of metal.
CONCLUSIONWhile preferred embodiments have been illustrated and described, it should be understood that the invention is not limited to these embodiments, but rather is defined by the accompanying claims.
Claims
1. A dowel assembly for use in for use in the formation of adjacent concrete slabs to maintain the slabs in alignment, comprising:
- a. a pocket forming member having a pocket therein, said member having an opening in one end communicating with the pocket;
- b. a dowel received within the pocket for movement between a first position fully confined within the pocket and a second position extending through the opening and partially out of the pocket; and,
- c. a fastener for securing the member to a form with the opening in apposition to the form and the dowel fully confined within the pocket.
2. A dowel assembly according to claim 1, further comprising a first stop on the pocket forming member for engagement with the dowel to limit the degree to which the dowel can be withdrawn from the pocket for movement to the second position.
3. A dowel assembly according to claim 2, further comprising a second stop on the pocket forming member for engagement with the dowel to prevent the dowel from moving from the second to the first position.
4. A dowel assembly according to claim 1, further comprising a latch interposed between the pocket member and dowel to lock the dowel in the second position upon movement of the dowel from the first position to the second position.
5. A dowel assembly according to claim 4, wherein the latch comprises:
- a. a spring biased pin carried by the dowel; and,
- b. a first pin receiving recess in the pocket member disposed for engagement by the pin upon movement of the dowel to the second position.
6. A dowel assembly according to claim 5, further comprising a second pin receiving recess in the pocket forming member for engagement with the pin to releasably secure the dowel in the first position, said second recess having a ramped surface to release the pin in response to force moving the dowel from the first position to the second position.
7. A dowel assembly according to claim 2, wherein:
- a. the pocket is of a generally rectangular configuration, as viewed in plan; and,
- b. the dowel is of a rectangular planar configuration generally complimental to that of the pocket.
8. A dowel assembly according to claim 7, wherein the dowel is width less than that of the pocket to allow limited lateral movement of the dowel relative to the pocket.
9. A dowel assembly according to claim 8, further comprising a resilient element engaged between the pocket and dowel to urge the dowel into alignment with the pocket while permitting limited lateral movement of the dowel relative to the pocket.
10. A dowel assembly according to claim 9, wherein:
- a. the resilient element comprises at least one detent engageable with a lateral edge of the dowel; and,
- b. the lateral edge of the dowel is formed with notches disposed for engagement with the detent to selectively secure the dowel in either the first or second position.
11. A dowel assembly according to claim 9, wherein the first stop comprises interengageable surface on the dowel and resilient element, disposed to engage one another when the dowel is moved to the second position.
12. A dowel assembly according to claim 1 wherein the opening is so disposed relative to the fastener that a form to which the fastener is secured covers the opening.
13. A dowel assembly according to claim 1, wherein the member comprises complimental upper and lower sections disposed for movement between an open condition exposing the pocket interiorly and a closed condition defining the pocket therebetween.
14. A dowel assembly according to claim 13, further comprising a hinge connection securing the upper and lower sections together for movement between the open and closed conditions.
15. A dowel assembly according to claim 13, wherein the upper and lower sections are of different depths and may be assembled in different combinations to alter the depth of the pocket formed therebetween.
16. A dowel assembly according to claim 13, further comprising a latch to secure the upper and lower sections in the closed condition.
17. A dowel assembly according to claim 13, wherein the fastener comprises flanges formed on the upper and lower sections for alignment to form a collar around the pocket forming member when the upper and lower sections are in closed condition.
18. A dowel assembly according to claim 17, further comprising apertures formed in elements carried by the respective flanges for alignment when the upper and lower sections are in closed condition, said elements being adapted to have a nail extended through the aligned apertures thereof to lock the sections in the closed condition and secure the collar formed by the flanges to a form element.
19. A dowel assembly according to claim 1, further comprising protrusions formed on the member interiorly of the pocket for engagement with the dowel to ease movement of the dowel between the first and second positions.
20. A dowel assembly according to claim 19, wherein:
- a. the dowel is disposed to move between the first and second positions in a generally rectilinear path; and
- b. the protrusions comprise ribs extending in a direction parallel to the path.
21. A dowel assembly according to claim 1, further comprising a closure element on the member to close the opening.
22. A dowel assembly according to claim 21, wherein the closure element comprises a door hingedly secured to the member to one side of the opening for movement between open and closed conditions relative to the opening.
23. A dowel assembly according to claim 22, wherein the door is hingedly secured to the member by a friable connection and the connection may be broken to completely remove the door from the member.
24. A dowel assembly according to claim 21, wherein the closure element comprises tape adhesively secured to the member.
25. A dowel assembly according to claim 1, wherein the fastener comprises a flange on the housing extending laterally of the opening.
26. A dowel assembly according to claim 25, wherein the flange comprises tabs disposed around the opening at spaced intervals.
27. A dowel assembly according to claim 25, wherein the flange comprises a collar extending around the opening.
28. A dowel assembly according to claim 1, further comprising a seal element mutually engaged between the pocket forming member and the dowel to seal the pocket against fluid intrusion when the dowel is in the second position.
29. A dowel assembly for use in for use in the formation of adjacent concrete slabs to maintain the slabs in alignment, comprising:
- a. a pocket forming member having a pocket therein of a generally rectangular configuration, as viewed in plan, said member having an opening in one end communicating with the pocket;
- b. a dowel received within the pocket for movement between a first position fully confined within the pocket and a second condition extending through the opening and partially out of the pocket, said dowel being of a rectangular configuration generally complimental to that of the pocket;
- c. a grip element on the dowel accessible through the opening to enable to dowel to be accessed for select manual movement between the first and second positions; and,
- d. a fastener for securing the member to a form with the opening in apposition to the form and the dowel fully confined within the pocket.
30. A dowel assembly according to claim 29, wherein the dowel is width less than that of the pocket to allow limited lateral movement of the dowel relative to the pocket.
31. A dowel assembly according to claim 30, further comprising a resilient element engaged between the pocket and dowel to urge the dowel into alignment with the pocket while permitting limited lateral movement of the dowel relative to the pocket.
32. A dowel assembly according to claim 31, wherein:
- a. the resilient element comprises a detent engageable with a lateral edge of the dowel; and,
- b. the lateral edge of the dowel is formed with notches disposed for engagement with the detent to selectively secure the dowel in either the first or second position.
33. A dowel assembly according to claim 31, further comprising interengageable surfaces on the dowel and resilient element disposed to stop the dowel when it moves from the first to the second position.
34. A dowel assembly according to claim 33, further comprising second interengageable surfaces on the dowel and resilient element to prevent the dowel from moving from the second to the first position.
35. A dowel assembly according to claim 29, wherein the opening is so disposed relative to the fastener that a form to which the fastener is secured covers the opening.
36. A dowel assembly according to claim 29, wherein the member comprises complimental upper and lower sections disposed for movement between a closed condition defining the pocket therebetween and an open condition exposing the pocket interiorly.
37. A dowel assembly according to claim 36, further comprising a hinge connection securing the upper and lower sections together for movement between the open and closed conditions.
38. A dowel assembly according to claim 36, further comprising a latch to secure the upper and lower sections in the closed condition.
39. A dowel assembly according to claim 29, further comprising protrusions formed on the member interiorly of the pocket for slidable engagement with the dowel to ease movement of the dowel between the first and second positions.
40. A dowel assembly according to claim 39, wherein:
- a. the dowel is disposed to move between the first and second positions in a generally rectilinear path; and
- b. the protrusions comprise ribs extending in a direction parallel to the path.
41. A dowel assembly according to claim 29, further comprising a closure element on the member to close the opening.
42. A dowel assembly according to claim 41, wherein the closure element comprises a door hingedly secured to the member to one side of the opening for movement between open and closed conditions relative to the opening.
43. A dowel assembly according to claim 42, wherein the door is hingedly secured to the member by a friable connection and the connection may be broken to completely remove the door from the member.
44. A dowel assembly according to claim 41, wherein the closure element comprises tape adhesively secured to the member.
45. A dowel assembly according to claim 29, wherein the fastener comprises a flange on the housing extending laterally of the opening.
46. A dowel assembly according to claim 45, wherein the flange comprises tabs disposed around the opening at spaced intervals.
47. A dowel assembly according to claim 45, wherein the flange comprises a collar extending around the opening.
48. A dowel assembly according to claim 29, further comprising a seal element engaged between the pocket forming member and the dowel to seal the pocket against fluid intrusion when the dowel is in the second position.
49. A method of forming adjacent concrete slabs with an dowel engaged therebetween to maintain the slabs in alignment, said method comprising:
- a. providing a pocket forming member having a pocket therein slidably receiving a dowel for movement between a first position fully confined within the pocket and a second position extending partially out of the pocket and through an opening formed in one end of the pocket;
- b. securing the pocket forming member to an edge forming member of a form, with the dowel fully confined within the pocket and the opening covered by the form;
- c. forming concrete against the forming member to provide a first concrete slab having the pocket forming member embedded therein with the opening disposed at one edge of the slab;
- d. removing the forming member to expose the opening;
- e. pulling a portion of the dowel partially out of the pocket; and,
- f. forming concrete against the one edge of the first concrete slab to provide a second slab having the portion of the dowel embedded therein.
50. A method according to claim 49, wherein a closure element is provided on the pocket forming member to cover the opening when the dowel is fully confined within the pocket and further characterized in that:
- a. when the pocket forming member is secured to the edge forming member of a form, the closure element is in place over the opening; and,
- b. when the forming member is removed, the closure element is also removed.
51. A method according to claim 49, wherein:
- a. the pocket forming member is secured to the edge forming member in a horizontal disposition and is of an expansive generally rectangular configuration, as viewed in plan; and,
- b. the dowel is of an rectangular configuration generally complimental to that of the pocket.
52. A method according to claim 49, further comprising providing a seal between the pocket forming member and dowel to seal the pocket against concrete intrusion during formation of the second slab.
53. A dowel for embedment in adjacent concrete slabs to maintain the slabs in alignment, said dowel comprising:
- a. a rigid body of a generally rectangular configuration, as viewed in plan, said body having side and end edges,
- b. a recess formed in the body and opening though an end edge thereof, said recess having a finger grip disposed therein.
54. A dowel according to claim 53, wherein:
- a. the recess comprises a notch formed in the end edge of the body through which the recess opens; and,
- b. the grip comprises a rib extending across the notch.
55. A dowel according to claim 54, wherein:
- a. the notch extends through the body and is of a trapezoidal configuration, as viewed in plan, with a narrow portion thereof at the edge of the body through which the recess opens and a wider portion thereof disposed internally of the body; and,
- b. the grip is formed on a member received within and complimental to the notch.
56. A dowel according to claim 54, wherein a detent notch is formed in a side edge of the body.
Type: Application
Filed: Oct 16, 2006
Publication Date: Oct 4, 2007
Applicant:
Inventors: Sidney E. Francies (Lithia, FL), David L. Kelly (Sacramento, CA)
Application Number: 11/582,473
International Classification: E01C 11/14 (20060101);