Strike Off Apparatus

Abstract

A strike off apparatus and method for moving a blade in such an apparatus are disclosed. The strike off apparatus may comprise a frame, a collar mounted to the frame, a blade mounted to the frame and moveable from a first position to a second position, a guide disposed within the channel, and an actuator operatively connected to the guide. The actuator may be configured to move the blade from the first position to a second position. The frame and collar may define a first portion of a generally vertical channel.

Description

TECHNICAL FIELD

The present disclosure generally relates to a strike off apparatus such as those disposed on paving machines and the like.

BACKGROUND

Typically, asphalt road paving machines have a hopper located at the front for receiving hot asphalt paving material and a conveyor for delivering the asphalt paving material from the hopper to the rear of the machine and depositing the asphalt onto the road surface to be paved. An auger is located at the rear of the machine for distributing some of the asphalt material laterally to the sides of the road surface. Such paving machines also include a screed and a strike off apparatus. The strike off apparatus is typically located between the auger and the screed. The screed is used to smooth out and compress the asphalt to the desired road mat thickness. The strike off apparatus(es) is/are used to distribute the paving material in front of the screed.

The strike-off apparatus includes a blade that is vertically adjustable. To adjust the blade, two manual screw actuators are typically utilized to move the blade up and down. The actuators are generally located at opposite ends of the blade. Both actuators must be turned at the same time, and at the same rate, otherwise binding of the blade occurs and the blade becomes “stuck.” Sometimes, a set of four guide slots may be used in conjunction with the pair of actuators to help guide the movement of the blade and limit blade deflection due to asphalt load. These guides can also contribute to binding of the blade if the blade is raised or lowered unevenly.

U.S. Pat. No. 6,174,105 issued Jan. 16, 2001 (the '105 Patent) incorporates a pair of threaded rods for raising and lowering a strike off blade. As shown in FIGS. 3-6 of the '105 Patent, each connective member includes a rod having a first end engaged with the strike off member and a second end engaged with the screed extension. The first end may have an exterior threaded portion that is threadably engaged with the strike off member. The disclosure states that two connective members are preferred because a device with a single connective member is less rigid or stable and devices with more than two connective members require an excessive amount of adjusting of the connective members. This type of strike off apparatus has the drawbacks discussed above. A better design is needed.

SUMMARY OF THE DISCLOSURE

In accordance with one aspect of the disclosure, a strike off apparatus is disclosed. The strike off apparatus may comprise a frame, a collar mounted to the frame, a blade mounted to the frame, a guide disposed within the channel, and an actuator operatively connected to the guide. The blade may be moveable from a first position to a second position. The actuator may be configured to move the blade from the first position to a second position. The frame and collar may define a first portion of a generally vertical channel.

In accordance with another aspect of the disclosure, a strike off apparatus mounted to a vehicle is disclosed. The strike off apparatus may comprise a frame, a collar mounted to the frame, the frame and collar defining a generally vertical channel, a blade mounted to the frame, a guide mounted to the blade and disposed within the channel, and an actuator operatively connected to the guide. The blade may be moveable from a first position to a second position. The actuator may be configured move the blade from a first position to a second position. The guide may include first and second generally parallel guide side edges.

In accordance with a further aspect of the disclosure, a method of moving vertically a blade in a strike off assembly is disclosed. The strike off apparatus may include a frame, the blade defining an aperture and mounted to the frame, a collar mounted to the frame, the frame and the collar defining a generally vertical channel, a guide disposed within the channel, and a pin disposed within the aperture. The blade may be moveable from a first position to a second position. The method may comprise moving the guide vertically within the channel from a first position to a second position, and guiding the blade movement by sliding the blade vertically on the pin in the aperture.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary strike off apparatus constructed in accordance with the teachings of this disclosure;

FIG. 2 is a cross-sectional view of the exemplary strike off apparatus of FIG. 1 when the blade is in an exemplary first position in which the blade is fully lowered;

FIG. 3 is a cross-sectional view of the exemplary strike off apparatus of FIG. 1 when the blade is in an exemplary second position in which the blade is fully raised; and

FIG. 4 is perspective view of a machine that incorporates the features of the present disclosure.

DETAILED DESCRIPTION

Referring now to the drawings, and with specific reference to FIG. 1, there is shown a strike off apparatus constructed in accordance with the present disclosure and generally referred to by reference numeral 100. FIGS. 2-3 illustrate cross-sectional views of the strike off apparatus 100 of FIG. 1. While the following detailed description and drawings are made with reference to a strike off apparatus 100 used on paving machines, the teachings of this disclosure may be employed on other industrial and paving machines.

FIG. 4 illustrates one example of a paving machine 200 that incorporates the features of the present disclosure. The paving machine 200 includes frame 202, an engine 204, a ground engaging assembly 206 and drive train components (not shown) mounted the frame 202. The ground engaging assembly 206 may be comprised of a track arrangement, wheels or the like. The frame 202 may include a cab assembly 208. The paving machine 200 may also include a hopper 210 for storing paving material disposed near the front of the machine 200, a screed 212 mounted to the frame 202 near the rear of the machine 200, an auger 214 and a strike off apparatus 100 mounted on the machine 200.

Turning now to FIGS. 1-3, the strike off apparatus 100 may comprise a frame 102, a collar 104 mounted to the frame, a blade 106, a guide 108 (FIGS. 2-3) and an actuator 110.

The frame 102 may include a body 112, a first sidewall 114, a second sidewall 116 and a top wall 118 disposed between the sidewalls 114, 116. The sidewalls 114, 116 and the top wall 118 may each be disposed generally perpendicular to the body 112. In one embodiment, the first and second sidewalls 114, 116 may be generally parallel to each other. The first sidewall 114 may be disposed proximal to a first edge 122 of the body 112 and the second sidewall 116 may be disposed proximal to a second edge 124 of the body 112. In one embodiment, each sidewall is fixedly secured to the body by welding, or the like. The top wall 118 may include a lip 120 that may overlap a portion of each sidewall 114, 116.

The frame 102 may also include a first elongated support member 126 and a second elongated support member 128. The first support member 126 may extend between the first sidewall 114 and the collar 104, and the second support 128 member may extend between the collar 104 and the second sidewall 116. The support members 126, 128 may be hollow or may be solid. In one embodiment, the support members 126, 128 may be fixedly mounted to the body by welding, or the like.

The body 112 of the frame 102 and the first sidewall 114 may define a first slit 130. The body 112 of the frame 102 and the second sidewall 116 may define a second slit 132. The first and second slits 130, 132 may each be configured to receive the blade 106.

The collar 104 may be mounted to the body 112 of the frame 102. The collar 104 may be fixedly secured to the frame 102 by welding, or the like. In one exemplary embodiment, the collar 104 may be a three sided structure with a perimeter that generally resembles a squared letter C (or a rectangle with one side removed.) The collar may have a primary side 138 and a secondary side 140. The body 112 of the frame 102 and the collar 104 may define a first portion 134 of a generally vertical channel 136 (see FIGS. 2-3). In some embodiments, the collar 104 may be generally centered on the frame 102 and the blade 106. In other embodiments, the collar 104 may be positioned elsewhere on the frame 102. For example, the collar 104 may be proximal to the center but may be closer to the first sidewall 114 than to the second sidewall 116. In another embodiment, the collar 104 may be proximal to the center but may be closer to the second sidewall 116 than to the first sidewall 114.

The blade 106 may be vertically moveable between a first 142 and a second position 144. The blade may define a first elongated aperture 146 and a second elongated aperture 148. In one embodiment, the apertures 146, 148 may be slot-like in shape. Other elongated shapes may also be utilized.

The blade 106 may be mounted to the body 112 of the frame 102. In one embodiment, the blade 106 may be generally flat. The strike off apparatus 100 may include a first attachment member 150 and a second attachment member 152. The first attachment apparatus 150 may extend through the first elongated aperture 146 in the blade 106 and through the body 112. Similarly, the second attachment apparatus 152 may extend through the second elongated aperture 148 in the blade 106 and through the body 112. In one embodiment, each of the first and second attachment apparatuses 150, 152 may include a spacer 151 and a pin 153 configured to extend through the blade 106 and body 112. Each pin 153 may be received in one of the elongated aperture 146, 148 and the blade 106 may be configured to slide on the pins 153. In other embodiments, other types of attachment apparatuses 150, 152 may be used that allow vertical movement of the blade.

The blade 106 and the collar 104 may define a second portion 154 of the vertical channel 136. The blade may also include first and second winged portions 156, 158. The first winged portion 156 may be slidingly disposed in the first slit 130. The second winged portion 158 may be slidingly disposed in the second slit 132.

The guide 108 may be disposed in the vertical channel 136. In one embodiment, the guide 108 may be generally flat and elongated in shape. The guide 108 may have first and second side edges 160, 162. In the exemplary embodiment illustrated in FIG. 2, the guide 108 is generally flat and the guide side edges 160, 162 are generally parallel and scalloped in shape. In other embodiments, the guide side edges may be other geometries than scalloped. The first guide edge 160 may be proximal to the primary side 138 of the collar 104. Similarly, the second guide edge 162 may be proximal to the secondary side 140 of the collar 104. In an embodiment, the guide 108 may define a window 164. The guide 108 may be mounted to the blade 106. In one embodiment, the window 164 may be disposed on the blade 106 and the guide 108 may be secured to the blade 106 by welding around the perimeter of the window 164.

The actuator 110 may be operatively connected to the guide 108. More specifically, the actuator 110 may be configured to move the blade 106 from a first position 142 to a second position 144. In one embodiment, the actuator may include a rod 166 and a pocket 168. The rod 166 may have a threaded portion 170. The pocket 168 may define an inner wall 172 having passageway threads 174 configured for mutual engagement with the threaded portion 170 of the rod 166. The pocket may be mounted to the guide 108. In one embodiment, the pocket 168 may be welded to the guide 108. Other methods of securing the pocket 168 to the guide 108 may be used. The actuator may also include a handle 176. The handle 176 may be configured to rotate the rod 166. Rotation of the rod 166 in one direction causes the pocket 168 and the attached guide 108 (and the blade 106 attached to the guide) to climb up the threaded portion of the rod 166. Rotation of the rod 166 in the opposite direction may cause the pocket 168 and the attached guide 108 (and blade 106) to climb down the threaded portion 170 of the rod 166. Other actuators, such as a ratchet assembly, may also be used to raise and lower the guide 108 in the vertical channel 136.

In one embodiment, the strike off apparatus 100 may also include a rib 178. The rib 178 may be secured to the first and second support members 126, 128. In some embodiments, the rib 178 may also be mounted to the first and second sidewalls 114, 116 and to the first and second support members 126, 127. The rib 178 may also be mounted to the body 112 and to the outside surface of the collar 104. The rib 178 may be mounted in a generally perpendicular orientation to the body 112 and the sidewalls 114, 116. The rib 178 may be mounted by welding, bolting, or the like.

A method of moving the blade 106 in the above described strike off assembly 100 is also disclosed. The method may comprise moving the guide 108 vertically within the channel 136, and guiding the blade 106 movement by sliding the blade 106 on the pins 153 disposed in the blade apertures 146, 148. The method may further comprise discontinuing upward movement of the blade 106 when the pins 153 are disposed at the lower end 180 (best seen in FIG. 2) of the aperture 146, 148. The moving step may be accomplished by rotating the threaded portion 170 of the rod 166 in the pocket 168 that is mounted on the guide 108. The pocket 168 defining an inner wall 172 having passageway threads 174 configured for mutual engagement with the threaded portion 170 of the rod 166.

INDUSTRIAL APPLICABILITY

The present disclosure may find applicability in reducing the likelihood that the blade 106 of a strike off apparatus 100 binds during vertical movement and in decreasing blade deflection during paving due to asphalt loading.

The blade 106 may be vertically raised and lowered. The actuator 110 is operably connected to the guide 108 to move the blade 106 from a first vertical position 142 to a second vertical position 144. The first and second positions 142, 144 may be any position between and including the fully lowered position and the fully raised position. The use of one single actuator 110 provides a single point of actuation 186 for raising and lowering the blade 106 of the strike off apparatus 100. This single point of actuation 186 eliminates binding of the blade 106 due to multiple actuator rods (or the like) being turned at different rates or asynchronously.

To raise the blade 106 the actuator 110 is activated. In one embodiment, the actuator 110 may be a screw actuator 110 including a handle 176, a threaded rod 166 and a pocket 168 having an inner wall 172 with passageway threads 174. Rotation of the handle 176 rotates the threaded rod 166. The handle 176 and rod 166 may be rotated in the clockwise and counterclockwise directions. When the rod 166 is rotated in a first direction the engagement of the threaded rod 166 and the threads 174 of the pocket 168 cause the pocket 168 to climb up the rod 166. Because the pocket 168 is mounted to the guide 108, the guide 108 moves up in the vertical channel 136 as the pocket 168 moves up the rod 166. The elongated geometry of the guide 108 provides for stability of the blade 106 during vertical movement and during paving.

The first and second guide edges 160, 162 steer the movement of the guide 108 in the channel 136 and provide for relatively even movement of the guide 108 in the channel 136. In some embodiments, the first and second guide edges 160, 162 may be scalloped edges, or similar geometry, in order to decrease surface friction between the primary and secondary sides 138, 140 of the collar 104 (more, specifically the inner wall of) and the guide 108.

Because the guide 108 is mounted to the blade 106, the blade 106 moves with the guide 108. As the blade 106 moves upward, the blade 106 slides on the pins 153 (or the like) that extend through the elongated apertures 146, 148 and the winged portions 156, 158 of the blade 106 slide upward in the slits 130, 132. Resistance of each pin 153 against the lower end 180 (best seen in FIG. 2) of the elongated aperture 146, 148 may limit the upward distance that the blade 106 may travel. Similarly, the resistance of the blade 106 against the peak 182 (best seen in FIG. 1) of the slits 130, 132 may limit the upward distance that the blade 106 may travel.

To lower the blade 106 the actuator 110 is activated. When the rod 166 is rotated in a second direction, opposite to the first direction, the engagement of the threaded rod 166 and the passageway threads 174 of the pocket 168 cause the pocket 168 to climb down the rod 166 and with it the guide 108 and blade 106.

Again, the first and second guide edges 160, 162 steer the movement of the guide 108 in the channel 136 and provide for relatively even movement of the guide 108 in the channel 136. In those embodiments in which the first and second guide edges 160, 162 are scalloped, or the like, the geometry of the guide edges 160, 162 decrease surface friction between the primary and secondary sides 138, 140 of the collar 104 (more, specifically the inner wall of) and the guide 108.

As the blade 106 moves downward the blade 106 slides on the pins 153 (or the like) extending through the elongated apertures 146, 148, and the winged portions 156, 158 of the blade 106 slide downward in the slits. Resistance of each pin 153 against the upper end 184 (best seen in FIG. 3) of the elongated aperture 146, 148 may limit how far the blade 106 may be lowered.

During paving, the collar 104 and the guide 108 provide increased structural support to the blade 106 to limit distortion of the blade 106 under asphalt (or the like) loads. The slits 130, 132 at either side of the strike off apparatus 100 provide support to the blade 106 to limit blade 106 deflection due to heavy asphalt loads. Similarly, the pins 153 and elongate aperture 146, 148 arrangements assist with the positioning of the blade 106 during movement and provide attachment to the frame for support during paving. The sidewalls 114, 116, support members 126, 128 and rib 178 also provide additional structural strength to withstand paving loads.

The features disclosed herein may be particularly beneficial to paving machines 200 that utilize strike off apparatus 100 to spread asphalt loads.

Claims

1. A strike off apparatus comprising:

a frame;

a collar mounted to the frame, the frame and collar defining a first portion of a generally vertical channel;

a blade moveable from a first position to a second position, the blade disposed between the collar and the frame;

a substantially flat guide disposed within the channel, the guide including a window therethrough, the window having a perimeter fixedly attached to the blade; and

an actuator operatively connected to the guide, the actuator configured to move the blade from the first position to the second position.

2. The strike off apparatus of claim 1, in which the frame includes a body, and first and second generally perpendicular, spaced apart, sidewalls disposed on the body.

3. The strike off apparatus of claim 2, wherein the first sidewall and the body define a first slit and the second sidewall and the body define a second slit, the first and second slits each configured to receive the blade.

4. The strike off apparatus of claim 2, in which the frame includes a first elongated support member and a second elongated support member, the first support member extending between the first sidewall and the collar, and the second support member extending between the collar and the second sidewall.

5. The strike off apparatus of claim 4, wherein the collar is generally centered on the frame.

6. The strike off apparatus of claim 1, wherein the blade and collar define a second portion of the vertical channel.

7. The strike off apparatus of claim 1, wherein the blade defines first and second elongated apertures.

8. The strike off apparatus of claim 1, in which the collar includes a primary side and a secondary side, and the guide includes a first guide side edge disposed proximal to the primary side of collar.

9. The strike off apparatus of claim 8, wherein the first guide side edge of the guide is scalloped.

10. The strike off apparatus of claim 1, in which the actuator includes a pocket and a rod having a threaded portion, the pocket defining an inner wall having passageway threads configured for mutual engagement with the threaded portion of the rod.

11. The strike off apparatus of claim 1, wherein the guide defines a window and the window is disposed on the blade.

12. A strike off apparatus mounted to a vehicle, the strike off apparatus comprising:

a frame;

a collar mounted to the frame, the frame and collar defining a generally vertical channel;

a blade disposed between the collar and the frame and moveable vertically between a first and second position;

a substantially flat guide mounted to the blade and disposed within the channel, the guide including a window therethrough and first and second generally parallel guide side edges, the window having a perimeter fixedly attached to the blade; and

an actuator operatively connected to the guide, the actuator configured move the blade from a first position to a second position.

13. The strike off apparatus of claim 12, in which the vehicle is a paving machine.

14. The strike off apparatus of claim 12, wherein the strike off apparatus has a single actuation point.

15. The strike off apparatus of claim 12, in which the blade defines an elongated aperture.

16. The strike off apparatus of claim 15, further including a pin received in the elongated aperture, wherein the blade is configured to slide on the pin.

17. The strike off apparatus of claim 12, wherein the guide is generally flat.

18. A method of moving vertically a blade in a strike off apparatus, the strike off assembly including a frame, the blade defining an aperture and disposed between a collar and the frame, the collar mounted to the frame, the frame and the collar defining a generally vertical channel, a substantially flat guide disposed within the channel, the guide including a window therethrough, the window having a perimeter fixedly attached to the blade, and a pin disposed within the aperture, the method comprising:

moving the guide vertically within the channel from a first position to a second position; and

guiding the blade movement by sliding the blade vertically on the pin in the aperture.

19. The method of claim 18, further comprising discontinuing upward movement of the blade when the pin is disposed at the lower end of the aperture, wherein the aperture is a slot.

20. The method of claim 18, wherein the activating step is accomplished by rotating a rod having a threaded portion in a pocket mounted on the guide, the pocket defining an inner wall having passageway threads configured for mutual engagement with the threaded portion of the rod.