Patent Application
20220325486
N/A
This invention relates generally to plows, and more particularly to improvements in snow plow and mount assemblies as well as to improvements in snow plows themselves.
Conventional pickup truck mounted snow plow assemblies have a mount frame that attaches to the truck frame below and behind the front bumper, and a snow plow frame that removably attaches to the mount frame. When not in use the snow plow frame is detached from the mount frame and stored; the mount frame remains on the truck frame but is generally unobtrusive as it is below and behind the front bumper.
A conventional snow plow frame has a lift frame and an A-frame. The lift frame removably attaches at its lower ends to the mount frame, and generally extends forwardly and upwardly from the mount frame. The A-frame is pivoted at its rearward end to the lower ends of the lift frame for pivoting about a transverse horizontal lift axis. A plow blade is pivoted to the A-frame at its forward end for pivoting about a vertical axis. Hydraulic cylinders are attached on one end to the blade and on the other end to the A-frame to pivot the blade about the vertical axis. The plow blade may also be pivoted to the A-frame for pivoting about a transverse horizontal blade trip axis, in the event that the snow plow employs a blade trip, or alternatively, a lower edge of the blade may be pivoted to the balance of the blade for pivoting about a transverse horizontal edge trip axis, in the event that the snow plow employs an edge trip. A hydraulic cylinder is operable between the lift frame and the A-frame to pivot the A-frame about the transverse horizontal lift axis and hence raise and lower the blade. There are at least two different types of lift arrangements.
One type of lift arrangement has a hydraulic cylinder attached on one end to the lift frame and attached on the other end to the A-frame. In this arrangement, retracting the cylinder directly raises the A-frame and blade, and extending the cylinder directly lowers the A-frame and blade. The other type of lift arrangement has a lift arm pivoted to the lift frame, a chain or cable or other tethering device attached on one end to the free end of the lift arm and attached on the other end to the A-frame, and a hydraulic cylinder attached on one end to the lift frame and attached on the other end to the lift arm. In this arrangement, extending the cylinder raises the A-frame and blade via the lift arm and chain, and retracting the cylinder lowers the A-frame and blade via the lift arm and chain.
Over the years a number of different hitching mechanisms have been proposed to allow an operator to more quickly and easily hitch the snow plow frame to the mount frame. Some examples of hitch assemblies are shown in the assignee's U.S. Pat. Nos. Re. 35,700, 6,928,757, 6,711,837, 6,526,577, 5,353,530, 7,797,859, 7,681,334, 7,430,821, 6,944,978, 6,615,513, 6,393,737, 6,276,076, and 6,178,669, the disclosures of which are hereby incorporated by reference herein as if fully set forth in their entirety.
A more recent development in the area of hitching mechanisms to allow an operator to more quickly and easily hitch the snow plow frame to the mount frame is shown in the assignee's U.S. Pat. No. 9,869,067, which is hereby incorporated by reference herein as if fully set forth in its entirety.
Current snowplow mount designs require the user to exit the vehicle during the plow attachment process to confirm plow to vehicle mount alignment, engage the plow retention device (hitch pins, latch, etc.), make the electrical connections for plow and lighting, and operate the snowplow stand. This process is again repeated during the plow detachment process. Requiring the user to exit the vehicle to perform the manual attach/detach process has multiple disadvantages. Exiting the vehicle increases the time required to attach/detach the plow and physical effort. The sequence of operations is subject to the user following the instructions, and can result in malfunctioning of the plow or inability to correctly achieve plow to vehicle connections. The user is exposed to hazards such as ergonomic factors from bending down and exerting force at operation points to achieve attachment. It exposes the user to hazards of having body parts in proximity to moving components, as well as environmental exposure (low temperature, wind, precipitation), and possible traffic hazards. Impaired visibility due to darkness or snow covering plow parts can make operation difficult and more time consuming, and affect the ability of the user to confirm correct connection has been established.
Despite the advances made in the area of hitching mechanisms over the years, further improvement is nevertheless desired to improve the speed, convenience, ergonomics, safety, and reliability of attaching/detaching the snow plow to/from the vehicle.
In one aspect, a snow plow and mount assembly comprises a mount frame adapted to be secured to a vehicle, a snow plow frame having an A-frame and a lift frame pivotally connected relative to one another for pivoting movement about a generally transverse horizontal axis, a plow blade pivotally connected relative to the A-frame for pivoting movement about a generally vertical axis, and a first actuator operably associated with the A-frame and lift frame for imparting relative pivoting movement between the A-frame and lift frame, the first actuator powered by an electrical system of the vehicle. One of the mount frame and lift frame has first and second arms and the other of the mount frame and lift frame has first and second receivers, the first and second arms received in respective ones of the first and second receivers upon relative movement therebetween towards one another. The lift frame has a latch mechanism and a second actuator for moving the latch mechanism to a latched position for securing the arms in the receivers and for moving the latch mechanism to an unlatched position for freeing the arms to move out of the receivers, the second actuator powered by the electrical system of the vehicle. The assembly is operable such that when the vehicle is driven toward the snow plow the arms are received in the receivers and an electrical connection is made between the vehicle electrical system and the first and second actuators without manual manipulation, when the first actuator is energized the lift frame pivots relative to the A-frame in a first direction to align the arms with the receivers, and when the second actuator is energized the latch mechanism is moved to the latched position thereby removably securing the snow plow frame to the mount frame.
Each arm can have a recess therein, and each receiver can have a hitch pin therein, the hitch pins received in respective ones of the recesses upon relative movement therebetween towards one another. The latch mechanism can comprise first and second latch pins, a hole in each arm and a corresponding hole in each receiver, for each latch pin. The assembly can be operable such that when the first actuator is energized the lift frame pivots relative to the A-frame in the first direction and the hitch pins are received in the recesses, the lift frame further pivots relative to the A-frame in the first direction and the arm holes are aligned with the receiver holes, and when the second actuator is energized the latch pins are moved to the latched position thereby positioning the latch pins in the arm holes and in the receiver holes.
The assembly can further comprise a sensor for sensing the latch pins are in the unlatched position and for sensing the latch pins are in the latched position. The sensor can directly or indirectly sense the position of the latch pins. If configured to directly sense the position of the latch pins, the sensor can be a contact sensor or a non-contact sensor.
The assembly can further comprise a support stand pivotally connected to the A-frame for pivoting movement to an extended ground contacting and snow plow frame supporting position and to a retracted position at which the support stand does not contact the ground and does not support the snow plow frame, and a mechanism for moving the support stand to the retracted position when the latch pins are in the latched position and for moving the support stand to the extended position when the latch pins are in the unlatched position.
The assembly can further comprise a support stand pivotally connected to the A-frame for pivoting movement to an extended ground contacting and snow plow frame supporting position and to a retracted position at which the support stand does not contact the ground and does not support the snow plow frame, the support stand biased toward the retracted position, the support stand having a cam surface thereon, and a cam actuating pin connected to the lift frame for translational movement between an extended position and a retracted position. The cam actuating pin can be operably associated with the support stand cam surface, and the second actuator can be operably associated with the cam actuating pin, such that when the second actuator is energized to move the latch pins to the unlatched position the cam actuating pin moves to the extended position, and when the first actuator is energized to pivot the lift frame relative to the A-frame in a second direction the cam actuating pin contacts the support stand cam surface whereupon further pivoting of the lift frame relative to the A-frame in the second direction moves the support stand to the extended position, and when the first actuator is energized to pivot the lift frame relative to the A-frame in the first direction the support stand returns to the retracted position, and when the second actuator is energized to move the latch pins to the latched position the cam actuating pin moves to the retracted position. The assembly can further comprise a link interconnecting the second actuator and the cam actuating pin.
The arms can be on the lift frame and the receivers can be on the mount frame.
The first actuator can be a hydraulic cylinder operably connected to the A-frame and to the lift frame, and the second actuator can be an electric linear actuator operably connected to the latch pins.
The mount frame can have one of a male connector and a female connector in electrical communication with the vehicle electrical system, and the lift frame can have the other of the male connector and the female connector in operable electrical communication with the first actuator and the second actuator; when the arms are received in the receivers the male and female connectors connect to make electrical contact. The connectors can be matingly tapered to facilitate connection in the event of misalignment. Each connector can include a permanent magnet to maintain connection of the connectors during shock and vibration of operation. The connectors can be mounted to the mount frame and lift frame in such a way to permit a degree of relative motion between the connectors and the mount frame and lift frame without breaking the electrical circuit established between the connectors. The female connector can be located on the mount frame, and further include a pair of pivoting covers which, when closed, prohibit entry of contaminates into the female connector, and when open, permit the female connector to connect to the male connector. The assembly can include a third actuator, energized by the electrical system of the vehicle, for opening the covers prior to attachment of the snow plow to the vehicle and for closing the covers subsequent to detachment of the snow plow from the vehicle.
The assembly can further include a sensor associated with the second actuator and a controller associated with the first actuator, the second actuator, and the sensor, the controller configured to prevent energization of the first actuator upon receiving a signal from the sensor that the second actuator is not fully extended. The sensor can be a linear encoder or a potentiometer providing a position signal of the second actuator to the controller.
The assembly can further include a sensor associated with the latch pins and a controller associated with the first actuator, the second actuator, and the sensor, the controller configured to energize the first actuator upon receiving a signal from the sensor that the arm holes and the receiver holes are not aligned so as to align the arm holes and the receiver holes. The sensor can sense a resistance force on at least one of the latch pins to determine that the arm holes and the receiver holes are not aligned. The second actuator can be an electric linear actuator connected to the latch pins, and the sensor can comprise a telescoping link assembly connected to the linear actuator and to one of the pins.
The telescoping link assembly can comprise a bracket mounted to the linear actuator and having first and second spaced apart ends and first and second limit switches mounted to the first and second ends, respectively, a telescoping link connected to the one pin, the link and bracket operable to telescope into and out of one another so as to shorten and lengthen, respectively, a collar mounted to the telescoping link, a first compression spring positioned between the first end of the bracket and the collar and a second compression spring positioned between the second end of the bracket and the collar, the compression springs normally biasing the collar to a nominal centered position between the first and second ends of the bracket, a first washer positioned between the collar and the first compression spring and a second washer positioned between the collar and the second compression spring. When the actuator is energized to extend and move the pins outwardly through the arm holes and the receiver holes, if one of the pins encounters a large enough resistance force due to misalignment of a respective arm hole and a respective receiver hole, the telescoping link assembly telescopes and the collar compresses a respective one of the first and second springs until a respective one of the first and second washers contacts a respective one of the first and second limit switches, activating the respective limit switch which deenergizes the linear actuator. At this time the first actuator is energized to pivot the lift frame relative to the A-frame so as to align the misaligned respective arm and receiver holes. Upon alignment of the misaligned respective arm and receiver holes, the compressed respective spring moves the one pin partially through the respective arm and receiver holes. At this time the one of the first and second washers moves out of contact with the respective one of the first and second limit switches, deactivating the respective limit switch which energizes the linear actuator to move the one pin to a fully engaged position.
The pins can be confirmed to both be in the fully engaged position when the linear actuator is fully extended, the first limit switch is not activated by the first washer, and the second limit switch is not activated by the second washer.
Alternatively, the sensor can sense a velocity or a current of the linear actuator to determine that the arm holes and the receiver holes are not aligned.
In another aspect, a snow plow and mount assembly comprises a mount frame adapted to be secured to a vehicle, a snow plow frame having an A-frame and a lift frame pivotally connected relative to one another for pivoting movement about a generally transverse horizontal axis, a plow blade pivotally connected relative to the A-frame for pivoting movement about a generally vertical axis, and a first actuator operably associated with the A-frame and the lift frame for imparting relative pivoting movement between the A-frame and the lift frame, the first actuator powered by an electrical system of the vehicle. One of the mount frame and the lift frame has at least a first arm and the other of the mount frame and the lift frame has at least a first receiver, the arm received in the receiver upon relative movement therebetween towards one another. The arm has one of a recess and a hitch pin therein, the receiver has the other of the recess and the hitch pin therein, the hitch pin received in the recess upon relative movement therebetween towards one another. The lift frame has a latch mechanism and a second actuator for moving the latch mechanism to a latched position for securing the arm in the receiver and for moving the latch mechanism to an unlatched position for freeing the arm to move out of the receiver, the second actuator powered by the electrical system of the vehicle. The latch mechanism comprises at least a first latch pin, a hole in the arm and a corresponding hole in the receiver. The assembly is operable such that driving the vehicle toward the snow plow causes the arm to be received in the receiver and an electrical connection to be made between the vehicle electrical system and the first and second actuators without manual manipulation, energization of the first actuator causes the lift frame to pivot relative to the A-frame in a first direction and the hitch pin to be received in the recess, further energization of the first actuator causes the lift frame to further pivot relative to the A-frame in the first direction to align the arm hole and the receiver hole, and energization of the second actuator causes the latch pin to move to the latched position thereby positioning the latch pin in the arm hole and in the receiver hole thereby removably securing the snow plow frame to the mount frame.
In another aspect, a snow plow and mount frame assembly permits an operator to attach a snow plow to a mount frame secured to a vehicle, without the operator exiting a cab of the vehicle. The assembly comprises first and second connectors on the mount frame and the snow plow, respectively, that connect during mating of the mount frame with the snow plow as the vehicle is driven toward the snow plow, to provide power to the snow plow from an electrical system of the vehicle, a first actuator powered by the vehicle electrical system to pivot a lift frame of the snow plow upwardly relative to an A-frame of the snow plow to align holes in the lift frame with holes in the mount frame, a second actuator powered by the vehicle electrical system to extend latch pins through the lift frame and mount frame holes to a latched position, a first sensor powered by the vehicle electrical system to determine that the lift frame and mount frame holes are aligned, a second sensor powered by the vehicle electrical system to determine that the second actuator is fully extended, and a controller that receives signals from the first and second sensors and sends signals to the first and second actuators in response to the signals received from the first and second sensors.
The assembly can further comprise a snow plow support stand operable to move from an extended position to a retracted position and from the retracted position to the extended position during energization of the first actuator to pivot the lift frame upwardly and downwardly relative to the A-frame, respectively, when the second actuator has the latch pins retracted in an unlatched position, and operable to not move from the retracted position to the extended position during energization of the first actuator to pivot the A-frame upwardly relative to the lift frame when the second actuator has the latch pins in the latched position.
The first actuator can be a hydraulic cylinder and the second actuator can be an electric linear actuator.
The first sensor can be a telescoping link assembly connected to the linear actuator and one of the pins. The telescoping link assembly can have first and second limit switches, wherein when if one of the pins encounters a large enough resistance force due to misalignment of a respective arm hole and a respective receiver hole, the telescoping link assembly telescopes and one of the first and second limit switches is activated deenergizing the second actuator, whereupon the first actuator is energized to align the misaligned respective arm and receiver holes, and upon alignment thereof the second actuator is energized to extend the one pin to a fully engaged position.
Alternatively, the first sensor can sense a velocity or a current of the linear actuator to determine that the arm holes and the receiver holes are not aligned.
The second sensor can be a linear encoder or a potentiometer.
When the first sensor senses that the arm holes and the receiver holes are aligned and when the second sensor senses that the linear actuator is fully extended, the hydraulic cylinder can be energized to pivot the A-frame upwardly relative to the lift frame. The first sensor senses that the arm holes and the receiver holes are aligned when neither of the first and second limit switches are activated.
In another aspect, a method permitting an operator to attach a snow plow to a mount frame secured to a vehicle, without the operator exiting a cab of the vehicle, comprises driving the vehicle towards the snow plow to mate the mount frame with a lift frame of the snow plow, establishing an electrical connection between an electrical system of the vehicle and the snow plow upon mating the mount frame with the lift frame, energizing a first actuator powered by the vehicle electrical system to pivot the lift frame upwardly relative to an A-frame of the snow plow to align holes in the lift frame with holes in the mount frame, energizing a second actuator powered by the vehicle electrical system to extend latch pins through the lift frame and mount frame holes to a latched position, and energizing the first actuator by the vehicle electrical system to pivot the A-frame upwardly relative to the lift frame.
The method can further comprise determining that the lift frame holes and the mount frame holes are aligned and that the latch pins are fully engaged in the lift frame holes and the mount frame holes, by one or more sensors powered by the vehicle electrical system, prior to energizing the first actuator to pivot the A-frame upwardly relative to the lift frame.
The method can further comprise raising a snow plow support stand from an extended position to a retracted position during energization of the first actuator to pivot the lift frame upwardly relative to the A-frame to align holes in the lift frame with holes in the mount frame.
The method can further comprise decoupling support stand movement from relative pivoting movement between the lift frame and the A-frame during energization of the second actuator to extend the latch pins through the lift frame and mount frame holes such that energizing the first actuator to pivot the A-frame upwardly relative to the lift frame does not cause the support stand to move from the retracted position to the extended position.
The method can further comprise lowering the support stand from the retracted position to the extended position during energization of the first actuator to pivot the lift frame downwardly relative to the A-frame.
The method can further comprise coupling support stand movement to relative pivoting movement between the lift frame and the A-frame during energization of the second actuator to retract the latch pins from the lift frame and mount frame holes.
In another aspect, a method permitting an operator to attach a snow plow to a mount frame secured to a vehicle, without the operator exiting a cab of the vehicle, comprises driving the vehicle towards the snow plow to mate the mount frame with a lift frame of the snow plow, establishing an electrical connection between an electrical system of the vehicle and the snow plow upon mating the mount frame with the lift frame, and energizing an actuator powered by the vehicle electrical system to actuate a latching mechanism to latch the lift frame to the mount frame.
In another aspect, a snow plow and mount assembly comprises a mount frame adapted to be secured to a vehicle, a snow plow frame having an A-frame and a lift frame pivotally connected relative to one another for pivoting movement about a generally transverse horizontal axis, a plow blade pivotally connected relative to the A-frame for pivoting movement about a generally vertical axis, a first actuator operably associated with the A-frame and the lift frame for imparting relative pivoting movement between the A-frame and the lift frame, the first actuator powered by an electrical system of the vehicle, one of the mount frame and the lift frame having first and second arms and the other of the mount frame and the lift frame having first and second receivers, the first and second arms received in respective ones of the first and second receivers upon relative movement therebetween towards one another, and the lift frame having a latch mechanism and a second actuator for moving the latch mechanism to a latched position for securing the arms in the receivers and for moving the latch mechanism to an unlatched position for freeing the arms to move out of the receivers, the second actuator powered by the electrical system of the vehicle. The assembly is operable such that when the vehicle is driven toward the snow plow the arms are received in the receivers and an electrical connection is made between the vehicle electrical system and the first and second actuators without manual manipulation, and when the second actuator is energized the latch mechanism is moved to the latched position thereby removably securing the snow plow frame to the mount frame.
In another aspect, a snow plow and mount assembly comprises a mount frame adapted to be secured to a vehicle, a snow plow frame having an A-frame and a lift frame pivotally connected relative to one another for pivoting movement about a generally transverse horizontal axis, a plow blade pivotally connected relative to the A-frame for pivoting movement about a generally vertical axis, a first actuator operably associated with the A-frame and the lift frame for imparting relative pivoting movement between the A-frame and the lift frame, the first actuator powered by an electrical system of the vehicle, and the lift frame having a latch mechanism and a second actuator for moving the latch mechanism to a latched position for securing the snow plow frame to the mount frame, the second actuator powered by the electrical system of the vehicle. The assembly is operable such that when the vehicle is driven toward the snow plow the snow plow frame mates with the mount frame and an electrical connection is made between the vehicle electrical system and the first and second actuators without manual manipulation, and when the second actuator is energized the latch mechanism is moved to the latched position thereby removably securing the snow plow frame to the mount frame.
The lift frame of the snow plow frame can mate with the mount frame.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the summary of the invention given above, and the detailed description of the drawings given below, serve to explain the principles of the present invention.
Referring first to
Referring now to
A-frame 22 comprises a pair of side frame members 60 connected together at their forward ends via a clevis 66 and a transverse frame member 62 interconnecting the side frame members 60 at their rearward ends. An angle section 64 (
A hydraulic cylinder 70 has one end mounted to the angle section 64 of the A-frame 22 and the other end mounted between the vertical frame members 58 of the lift frame 24. A hydraulic motor and pump assembly 72 for powering the hydraulic cylinders 40 and 70 is mounted to the side frame members 50 and the intermediate frame member 54 of the lift frame 24.
A support stand 74 is movably mounted to the A-frame 22, for example for pivoting movement or translational movement or both. As one example, the stand 74 can be pivotally mounted to the angle 64 at 76. Stand 74 pivots to an extended ground or pavement contacting and snow plow frame 20 supporting position and to a retracted position at which the stand 74 does not contact the ground or pavement and does not support the plow frame 20. The stand 74 is biased, for example spring biased, to the retracted position by a torsion spring 78. As used herein, the terms “ground” and “pavement” shall be deemed to be interchangeable and shall be deemed to embrace such surfaces whether the surfaces are snow and/or ice covered or bare.
The lower end of each upstanding frame member 50 of the lift frame 24 has a rearwardly extending arm 80. Each arm 80 can be, but is not necessarily required to be, comprised of a pair of spaced apart plates 82, 84. The end of each arm 80, and as illustrated the end of each plate 82, 84, has a flat 86 formed thereon and a forwardly extending recess 88 formed therein above the flat 86. The inner plates 84 of the arms 80 are interconnected with a transverse frame member 90. The plates 82, 84 making up each arm 80 have holes 92, 94, respectively. The holes 92, 94 have a latch pin 100 that travels in them from an inward unlatched position to an outward latched position.
The latch pins 100 are connected to opposite ends of an electric linear actuator 102. Each latch pin 100 has a guide bracket 104 associated therewith cantilevered off of its respective plate 84. Each guide bracket 104 includes a transversely oriented guide slot 106 therein. Each guide slot 106 guides the lower end of a connecting bolt or pin 108 connecting one of the latch pins 100 to a respective end of the linear actuator 102, to guide and assist the latch pins 100 in moving through the various latch holes.
The support stand 74 has a cam surface 109 thereon. A cam actuating pin 110 is mounted to the lift frame 24 for translational movement in a transverse direction between an extend position and a retracted position. A link 112 has one end connected to an end of the pin 110 and the other end connected to the linear actuator 102.
Mount frame 30 is adapted to be mounted to the frame of a pickup truck generally below and generally behind the front bumper, and has a pair of spaced apart receivers 140 interconnected by transverse frame member 142. Each receiver 140 has an inner plate 144, an outer plate 146, and an intermediate plate 148. Each receiver 140 has a hitch pin 152 positioned in a lower region and interconnecting the three plates 144, 146, 148 making up the receiver 140. The outer plates 146 have a latch hole 156 therein, and the intermediate plates 148 have a latch hole 158 therein. Each inner plate 144 has a recess 150 therein which partially encircles its respective latch pin 100 when latched.
Note that while the lift frame 24 has been described as having the arms 80 and the mount frame 30 has been described as having the receivers 140, it is within the scope of the invention that the lift frame 24 has the receivers 140 and the mount frame 30 has the arms 80. Note also that while the lift frame 24 has been described as having a pair of arms 80 and the mount frame 30 has been described as having a pair of receivers 140, it is within the scope of the invention that the snow plow and mount assembly has a single arm and a single receiver. For example, the single arm could be a plate spanning the width of the lift frame 24 and the receiver could be a box section or a pair of facing C-sections, etc. spanning the width of the mount frame 30, and sized for receiving the plate. As well, the single arm could be on either the lift frame 24 or the mount frame 30, and the receiver could be on the other of lift frame 24 and the mount frame 30.
Referring to
When the arms 80 are received in the receivers 140 the male and female connector portions 162, 164 connect to establish the electrical circuit via contacts 167, 169. As illustrated, the connector portions 162, 164 can be matingly tapered to facilitate connection in the event of misalignment. Each connector portion 162, 164 can include a respective permanent magnet 163, 165 to maintain connection of the connector portions 162, 164 during the shock and vibration of operation. A sealing element 171 helps to keep debris from entering the interior of the connector 160 and assists in keeping the contacts 167, 169 clean so as to establish and maintain electrical connectivity. The connector portions 162, 164 can be mounted to the lift frame 24 and the mount frame 30 in such a way to permit a degree of relative motion between the connector portions 162, 164 and the lift frame 24 and the mount frame 30 without breaking the electrical circuit established between the connector portions 162, 164. For example, a bracket 166 can be used to mount the male connector portion 162 to transverse member 90, which bracket 166 can include as many as six degrees-of-freedom of relative movement between the connector 162 and transverse member 90. Similarly, a bracket 168 can be used to mount the female connector portion 164 to transverse member 142, which bracket 168 can also include as many as six degrees-of-freedom of relative movement between the connector 164 and the transverse member 90. The relative movement of each connector portion 162, 164 relative to its respective transverse frame member 90, 142 can be supplied via the use of bolts riding in slots, springs, resilient material (such as elastomeric material, etc.), and the like.
The female connector portion 164 can further include a pair of pivoting covers 170 which, when closed, prohibit entry of contaminates into the female connector portion 164, and when open, permit the female connector portion 164 to connect to the male connector portion 162. An electric linear actuator 172, energized by the electrical system of the vehicle and activated from inside the cab of the vehicle, opens the covers 170 prior to attachment of the snow plow frame 20 to the mount frame 30, and closes the covers 170 subsequent to detachment of the snow plow frame 20 from the mount frame 30. Each cover 170 includes a pin 174 that rides in a respective angled guide slot 176 in a plate 178 connecting the actuator 172 to the covers 170. A retaining guide block 179 is attached to a forward end of the linear actuator 172 via fasteners. The plate 178 also has a centrally located and longitudinally oriented guide slot 181. Guide block 179 slides longitudinally relative to the guide slot 181. Retraction of the actuator 172 causes closing of the covers 170 as pins 174 ride forwardly in slots 176; extension of the actuator 172 causes opening of the covers 170 as pins 174 ride rearwardly in slots 176.
Referring now to
Initially, cam actuating pin 110 is in its deployed position, and in contact with the cam surface 109 on the stand 74. As the lift frame 24 pivots, upward movement of the cam actuating pin 110 allows the bias of the spring 78 on the stand 74 to pivot the stand 74 counterclockwise (as viewed in
With the holes 92, 94, 156, 158 aligned, the operator activates a latch switch from inside the cab to energize and extend the electric linear actuator 102 to move the latch pins 100 outwardly through holes 94, 148, 92, and 146 in that order to the latched position, thereby removably securing the plow frame 20 to the mount frame 30 (
Unhitching the plow frame 20 from the mount frame 30 is essentially the reverse of the above. The truck is parked. The operator activates the lift switch to retract the hydraulic cylinder 70 to lower the plow blade 34 until it is supported on the ground or pavement. The operator activates the latch switch to retract the linear actuator 102 thereby moving the latch pins 100 inwardly through holes 146, 92, 148, and 94 in that order to the unlatched position. Retraction of the actuator 102 to the unlatched position moves the pin 110 to its extended position. The operator again activates the lift switch to further retract the hydraulic cylinder 70 pivoting the lift frame 24 counterclockwise (as viewed in
As shown in
The above description generally assumes that the holes 92, 94 in the plates 82, 84 of the arms 80 are aligned with the holes 156, 158 in the plates 146, 148 of the receivers 140 during latching and unlatching, i.e. the best-case scenario. In all likelihood, there will be some misalignment between the arms 80 and receivers 140, the result being that the latch pins 100 will bind up during extension by the actuator 102 to the latched position or during retraction by the actuator 102 to the unlatched position. Accordingly, the assembly preferably includes various sensors working in tandem with the actuators, and a controller which receives signals from the sensors and which controls the actuators based on those signals, to accomplish latching and unlatching.
More particularly, and referring now to
The second sensor 210 can be a linear encoder or a potentiometer associated with (i.e. either made as a part of, or made separate from but electrically connected to) electric linear actuator 102, supplying a signal to the controller 202 that the linear actuator 102 is fully extended and hence the latch pins 100 are in their fully extended and latched position.
The first sensor 208 can sense a resistance force on at least one of the latch pins 100 indicating that the holes 92, 94 are misaligned relative to the holes 156, 158. Upon receiving a signal from the first sensor 208 that the holes 92, 94 and 156, 158 are misaligned, the controller 202 is configured to energize the hydraulic cylinder 70 (to either extend or retract or extend and retract the hydraulic cylinder 70) so as to align the holes 92, 94 and 156, 158. Once the holes 92, 94 and 156, 158 are aligned, the controller 202 de-energizes the hydraulic cylinder 70 and re-energizes the linear actuator 102 to completely extend the linear actuator 102 and hence completely extend the latch pins 100 to their fully extended and latched position.
Referring now to
A collar 326 encircles the cylinder 312 and is pinned to the end of the telescoping link 320 via a bolt or pin 328 which is oriented perpendicularly to and extends through the slot 318 in the cylinder 312. A first compression spring 330 is positioned between the first spring stop 314 of cylinder 312 and the collar 326. A second compression spring 332 is positioned between the second spring stop 316 of cylinder 312 and the collar 326. A first washer 334 is positioned between the collar 326 and the first compression spring 330 and a second washer 336 is positioned between the collar 326 and the second compression spring 332.
The compression springs 330, 332 normally bias the collar 326 to a nominal centered position between the first 314 and second 316 spring stops of the bracket 302. The bracket 302 further includes an arm 340 having an end 342. The end 342 has a width approximately the same width as the collar 328, and maintains the springs 314 and 316 in their nominally centered position.
As shown in
As shown in
As shown in
Note that whether the linear actuator 102 is energized so as to extend and hence extend the latch pins 100 to their latched position and one of the pins 100 fails to move to the fully extended and latched position due to misalignment of the holes 92, 94 and 156, 158, or whether the linear actuator 102 is energized so as to retract and hence retract the latch pins 100 from their latched position and one of the pins 100 fails to move to the fully retracted and unlatched position due to misalignment of the holes 92, 94 and 156, 158, the telescoping link assembly 300, linear actuator 102, hydraulic cylinder 70, and controller 202 work in a similar manner in both instances to detect and alleviate misalignment of the holes 92, 94 and 156, 158. In the case of the former, the energy of the compressed compression spring will partially extend the latch pin 100 through the holes 92, 94 and 156, 158 (once aligned), and the linear actuator 102 will be re-energized so as to completely extend the latch pins through the holes 92, 94 and 156, 158 to their latched position. In the case of the latter, the energy of the compressed compression spring will partially retract the latch pin 100 from the holes 92, 94 and 156, 158 (once aligned), and the linear actuator 102 will be re-energized so as to completely retract the latch pins from the holes 92, 94 and 156, 158 to their unlatched position.
In order to better visualize operation of the telescoping link 300, when either the left hand (driver side) or the right hand (passenger side) latch pin 100 binds up during extension of the linear actuator 102 to move the latch pins 100 to the latched position, the left hand (first) compression spring 330 is compressed (telescoping link assembly 300 telescopes inwardly), and when either the left hand (driver side) or the right hand (passenger side) latch pin 100 binds up during retraction of the linear actuator 102 to move the latch pins 100 to the unlatched position, the right hand (second) compression spring 332 is compressed (telescoping link assembly 300 telescopes outwardly).
The latch pins 100 can be confirmed to both be in their fully engaged or latched position when the linear actuator 102 is fully extended as indicated by second sensor 210, the first limit switch 308 is not activated by the first washer 334, and the second limit switch 310 is not activated by the second washer 336. When this state is communicated to the controller 202 by the first 208 and second 210 sensors, the controller 202 permits plowing to commence by permitting the hydraulic cylinder 70 to raise and lower the A-frame 22 and hence plow blade 34 relative to the lift frame 24 in response to activation of the in-cab lift switch by the operator.
Alternatively, the first sensor 208 could sense a velocity or a current of the linear actuator 102 to determine that the arm holes 92, 94 and the receiver holes 156, 158 are not aligned.
Referring to
Note that while a single linear actuator 102 has been shown which extends and retracts both latch pins 100, the invention could also be practiced with a pair of linear actuators, each associated with a respective one of the latch pins 100. The pair of linear actuators could move the latch pins 100 simultaneously or in seriatim.
Note also that while the position of the latch pins 100 has been described as being sensed indirectly via the telescoping link assembly 300, the position of the latch pins 100 could also be sensed directly. For example, non-contact sensors such as “Hall effect” sensors or magnetic reed switches could be utilized. As another example, contact sensors such as proximity switches or limit switches could be utilized.
Note further that while the operation of the snow plow assembly has been described in the context of the operator activating one or more switches inside the cab of the vehicle during various stages of latching and unlatching, the control system 200 could be configured to automatically perform all the steps required to latch the lift frame 24 to the mount frame 30 upon a single activation of a switch, and perform all the steps required to unlatch the lift frame 24 from the mount frame 30 upon a single activation of a switch. For that matter, the control system 200 could be configured to automatically perform all the steps required to latch the lift frame 24 to the mount frame 30 upon an electrical connection being made between the male portion 162 and the female portion 164 of the connector 160, without an operator activating any switch.
Note still further that while the assembly has been described as having the lift frame 24 of the plow frame 20 connected to the mount frame 30, the invention can also be practiced with the A-frame 22 of the plow frame 20 connected to the mount frame 30. Such a configuration is shown in the assignee's U.S. Pat. No. RE35,700, hereby incorporated by reference herein as if fully set forth in its entirety, wherein it will be seen that the A-frame is pinned to the mount frame and the lift frame is pinned to the A-frame.
The improved snow plow and mount assembly provides drive-in alignment, establishes the electrical connection between the vehicle and snow plow, provides remote actuated hitch pins, and provides automatic stand operation, all controlled from inside the vehicle. These functions eliminate operator error in the attachment/detachment process, insure correct attachment/detachment, reduce operator exposure to hazards, and generally provide quicker and easier operation, all the while permitting the operator to remain inside the vehicle.
The various embodiments of the invention shown and described are merely for illustrative purposes only, as the drawings and the description are not intended to restrict or limit in any way the scope of the claims. Those skilled in the art will appreciate various changes, modifications, and improvements which can be made to the invention without departing from the spirit or scope thereof. The invention in its broader aspects is therefore not limited to the specific details and representative apparatus and methods shown and described. Departures may therefore be made from such details without departing from the spirit or scope of the general inventive concept. The invention resides in each individual feature described herein, alone, and in all combinations of any and all of those features. Accordingly, the scope of the invention shall be limited only by the following claims and their equivalents.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 16452799 | Jun 2019 | US |
| Child | 17809095 | US |
