JPH08156752A - Landing leg for trailer and trailer equipped therewith - Google Patents

Abstract

PURPOSE: To automatically raise or lower a leg, as when connecting a trailer to a tractor, by transmitting a driving force from an air pressure motor to the lower portion of the leg via appropriate transmission means, for displacing the lower portion vertically relative to the upper portion so as to increase or decrease the overall length of the leg. CONSTITUTION: A landing leg 10 of a trailer is constructed of an upper portion 12 and a lower portion 14 which fits into the upper portion 12, and a bottom portion 16 is disposed at the lower end of the lower portion 14. The upper portion 12 is attached to the chassis of the trailer via a flange 18. A reversible air pressure motor 62 for driving one chain wheel 58 is disposed on a side face member 28 of a housing 22 attached to the upper portion 12. Quick air relief valves 68, 70 are disposed respectively on the side face member 28 and its bracket 72. A driving force is transmitted from the reversible air pressure motor 62 via an appropriate transmission means for the lower portion 14 of the leg 10 so as to displace the lower portion 14 vertically relative to the upper portion 12 to increase or decrease the overall length of the leg 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a landing leg for a trailer and a trailer including the same.

[0002]

BACKGROUND OF THE INVENTION Trailer-tractor combinations are widely used and the connection between the tractor and the trailer is the so-called fifth wheel and kingpin. When the tractor is disengaged from the trailer, the trailer's telescopic landing legs are extended within a short distance from the surface of the trailer-tractor combination. The trailer electrical circuit, main braking line and emergency braking line are then disconnected from the corresponding lines on the tractor. When the fifth wheel is removed from under the kingpin, the trailer settles on its landing leg. When reconnecting the trailer and tractor, the tractor is supported so that the fifth wheel and kingpin disengage while lifting the trailer from the landing foot, which allows the landing foot to be lifted. Then the electrical circuit and the brake line are connected.

All commercially available landing legs known to the Applicant are manual. The driver uses the crank handle,
The input gear of the transmission is driven to raise and lower the movable member of the landing leg according to the direction in which the crank handle is turned.

Various proposals for driving landing legs have been proposed, and by way of reference, US Pat. No. 4,097,840.
Discloses a method involving an electric motor, US Pat.
9,829 discloses a pneumatic system, and US Pat.
41,179 discloses a hydraulic system. All of these types have operating means such as valves and bush buttons that must be operated by the driver to raise and lower the landing legs.

Applicant is unaware of a commercially available system that does not use telescopic landing legs. However, US Pat.
696 discloses a format in which each landing leg is pivotally mounted at its upper end to the track body. A tilted air cylinder mounted between the leg and the truck body moves the leg between a vertical position in use and a retracted position which is about 45 degrees to the horizon. The trailer has a storage tank for compressed air and a valve connecting the tank to the upper end of the cylinder for displacing the landing leg to the retracted position and connecting the tank to the lower end of the cinder to displace the landing leg to its vertical position. . The valve itself is displaced between two positions by pressurizing and depressurizing air within the emergency brake line. When the trailer is uncoupled, the air pressure in the emergency brake line is reduced and the valve is in a position where air is supplied to the top of the cylinder to lower the landing feet. When the trailer is re-engaged, the air pressure in the emergency brake line causes the valve to move to another position in the emergency brake line, causing air to be supplied from the storage tank to the lower end of the cylinder and retract the landing feet.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to have a structure in which air flows to one side of a motor to lift the legs and flows in the opposite direction to lower the legs, each relief valve being connected to opposite sides of the motor. And air can flow from any valve to the motor and can be released from the motor through any valve into the atmosphere, and when the trailer is connected to the tractor, air to lift the legs Is taken from the trailer's emergency brake line, and when uncoupled, the emergency brake line is connected to the emergency air brake air reservoir, so air for lowering the legs can be manually or automatically taken from the air reservoir Is to provide a trailer landing leg.

[0007]

According to one aspect of the invention, a landing leg of a trailer has an upper portion having means for mounting the leg on the trailer and is movable relative to the upper portion, thereby allowing the leg to move. A lower portion that increases or decreases in length, a pneumatic motor having first and second inlets and outlets that directly connect the pneumatic motor to the air line so that air flowing in the air line can flow through the motor in either direction, and An air rapid relief valve connected to an air line on one of each side of the motor, each valve having first and second inlets and outlets and an outlet for flowing air into the atmosphere, and An air rapid relief valve connected to keep the air flowing to the pneumatic motor while the valve discharges the air from the pneumatic motor to the atmosphere, and transmits the driving force from the pneumatic motor to the lower part; Ri, is displaced upward direction of the lower to the upper, and the driving force transmitting means for increasing or decreasing the length of the leg,
including.

It should be noted that the landing leg of the trailer has an operating member arranged so as to be engaged when the lower portion is lifted, so that the lifting of the lower portion is terminated when the lower portion is lifted. It is preferable to include a valve for switching the passage of air from the pneumatic motor.

Further, it is preferable that the transmission means of the landing leg of the trailer is the deceleration transmission means, whereby the rotation of the output shaft of the pneumatic motor slows down the rotation of the output shaft of the transmission means.

Further, the transmission means includes a small chain wheel driven by the output shaft of the pneumatic motor, a large chain wheel driven by a chain wound around both wheels, and a series driven by a large chain wheel. It is also preferable to include a gear wheel.

Further, the tractor has an emergency brake line connected to an air reservoir for emergency brake operation which is filled when the trailer is connected with the tractor and is emptied when the trailer is separated from the tractor. A hose coupling to the air system of claim 1, and a landing leg as defined in claim 1 having an upper portion mounted to the trailer, the air line being connected to the emergency braking line at one end and the air being connected at the other end. More preferred is one that is tethered to an air reservoir for reception.

In accordance with a second aspect of the invention, a trailer has a landing portion having an upper portion mounted to the trailer and a lower portion that can be moved relative to the upper portion to increase or decrease the length of the landing legs. A leg, a pneumatic motor having first and second inlets and outlets connecting the pneumatic motor to the air line so that air flowing in either direction through the pneumatic line flows through the pneumatic motor, and each side of the pneumatic motor A rapid air relief valve connected to the air line with one of the valves, each valve having first and second inlets and outlets and an outlet for flowing air into the atmosphere, and each valve being a pneumatic motor. Air relief valve connected to keep the air flowing to the pneumatic motor while the air is being discharged from the air to the atmosphere, and the driving force is transmitted from the pneumatic motor to the lower part, so that the lower part is connected to the upper part. Drive force transmission means for vertically changing the length of landing legs, an emergency brake line connected to the air reservoir for emergency brake operation, a hose coupling connecting the emergency brake line to the tractor's air system, and a brake. An air inlet in the line,
It has an air outlet and an adjustment port, is a relay valve in the middle of the coupling and the air reservoir, and is operated in the lower part so that the lower part is lifted, and is in the middle of the emergency brake line and the first emergency relief valve, And a relay valve that is operated by lifting the lower part, which helps to switch the air from the pneumatic motor to the adjusting port of the relay valve when the relay valve is opened and air can flow to the air reservoir, A second relay valve having an inflow port, an outflow port, and an adjusting port, wherein the adjusting port is connected to the emergency brake line, the second relay valve is closed by the pressure in the emergency brake line, and the air of the second relay valve is closed. The outlet is connected to the second of the discharge valves and the air inlet of the second relay valve is connected to the air reservoir, whereby the emergency braking line is disconnected from the tractor Drops the pressure in the emergency brake in the line is, the air reservoir air flows into air motor, the second
Relay valve of.

It should be noted that the second relay valve is replaced by a manually operated valve connected between the air reservoir and the second valve of each emergency relief valve, whereby operation of the manually operated valve causes the landing leg to land. Preferably, air is supplied to the pneumatic motor from an air reservoir so that

[0014]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is an external view of an embodiment of the landing leg of the present invention, FIG. 2 is a top view with the housing of FIG. 1 removed, and FIG. 3 is a side view of the upper portion of FIGS. 4 is a side view of the inside of the housing of FIG. 1, FIG. 5 is a front view of the bracket,
FIG. 6 is an enlarged bottom view of the bracket of FIG. 5, and FIG.
FIG. 7 is a diagram showing an air circuit system of the landing leg from FIGS.

FIG. 1 shows a landing leg generally designated by the reference numeral 10 and including an upper portion 12 and a lower portion 14. The upper part 12 is composed of a vertical elongated cylinder having a hollow square cross section. The lower portion 14 is comprised of a rod of square cross section that fits snugly within the barrel forming the upper portion 12. At the lower end of the lower part 14 is the bottom part 1 which is the component that engages the surface on which the trailer stands
There is 6.

The protrusions from the two corners of the upper part 12 are the flanges 18, of which only one is visible in FIG. Flange 18
Near the top end (see FIG. 2) is a series of bolt holes 20. Bolts through these holes attach the landing leg 10 to the trailer chassis. A housing, generally designated by the reference numeral 22, is attached to the upper portion 12. More specifically, the housing includes a front member 26 and a side member 2.
8 includes a plate 24 (FIG. 2) that is bent to include 8. The bracket 30 is one limb (1 imb) to which the side member 28 is attached and the adjacent flange 18 of the upper part 12.
Has other limbs attached to each bolt 32. Two of the bolt holes 20 receive bolts 32. The centerline of one of the bolts passing through each bolt hole 20 and attaching the landing leg to the chassis is shown at 34, but the chassis itself is not shown.

The split housing 36 has a gearing therein. The gearbox output shaft in housing 36 is designated by the reference numeral 38 and the transmission input shaft is designated by the reference numeral 40.

Upper part 12 for displacing lower part 14 in the vertical direction
The transmission device therein is not shown in detail, but may be selected from a number of conventional shapes. For example, it may be a rack fixed to the lower portion 14 and a pinion driven by the output shaft 38. Alternatively, it may be a crown gear at the upper end of the vertical shaft and a pinion driven by the shaft 38 to drive the crown gear. Due to the rotation of the vertical shaft, the nut that is fixed to the lower part and is not rotated moves up and down according to the direction of rotation, moving the lower part together.

A shaft 42 of square cross section projects from the upper part 12 and is connected by a lateral shaft to the landing leg on the other side of the trailer. The shaft 42 is rotated by the shaft 38, and thus each landing leg is simultaneously retracted and extended.

In FIG. 3, reference numeral 44 designates a disk 4 coaxial with the input shaft 40 and having a sleeve 48 protruding therefrom.
6 shows a chain wheel 44 fixing 6 (see also FIG. 1). The input shaft 40 extends inside the sleeve 48. A cross pin can be inserted into the hole 48 ₁ (FIG. 4) of the sleeve 48 and the corresponding hole of the shaft 40 so that the sleeve and the shaft are fixed to each other during rotation.

Three studs 50 for fixing the chain wheel 44 project through three holes formed in the disk 46. Three thumbscrews 52 secure the disc 46 to the chain wheel 44. The chain 54 is mounted around the chain wheel 44 and further around two chain wheels 56 and 58. The chain wheel 56 is moved by a chain tensioner 60 and the chain wheel 58 is driven by a pneumatic motor, which will be described in detail below.

By manipulating the handle of the shaft 40, the landing leg can be manually moved up and down.

In FIG. 4, the inner surface of the side member 28 is shown and
Excluding the upper part 12 of the ground leg 10 and the transmission housing 36
The rest is shown. Attach the plate 24 to the flange 18.
The mounting bracket 30 is shown in FIG.
Two bolt holes 30 to insert ₁ Having.

Reference numeral 62 indicates a reversible pneumatic motor for driving the chain wheel 58. The pneumatic motor 62 is mounted on the front member 26 by a bracket 64.
It is suspended from below. The air inlet / outlet from the pneumatic motor 62 is indicated by reference numeral 66.

Reference numbers 68 and 70 designate two quick relief valves (also referred to as exhaust valves) which ensure that air is rapidly expelled from the system when needed. The valve 68 is mounted on a bracket 72 which is fixed to the side member 28, and the valve 70 is mounted directly on the side member 28. Thus, in FIG. 4, valve 68 is shown from the side and valve 70 is shown from the end.

The valves 68 and 70 are conditioned to allow air to flow through the second inlet / outlet when air pressure is applied to the first inlet / outlet. However, when pressure is applied to the second inlet / outlet, the valve switches and air does not flow to the first inlet / outlet, but flows into the atmosphere.

Three air connections 74, 76 and 78 are shown. These air connections connect to three hoses 80, 82 and 84 (FIG. 3) extending from the landing leg. The connection of these hoses to this system and the remaining pneumatic connections are described in detail below with respect to FIG.

In FIGS. 5 and 6, reference numeral 86 is the upper part 1.
2 shows the bracket at the bottom of the bolt shown. The centerline of each bolt connecting bracket 86 to flange 18 is shown at 88. The bracket 86 is not shown in FIG.

Affixed to bracket 86 is a plate 90 which forms a bending platform 92 with the upper edge of the plate perpendicular to the rest of the plate. Platform 92 cut into one end 3
Has three notches 94, these three hoses 99, 9
8,100 pass through these notches.

The notched plate 102 is a stud 10
At 4, the hoses 96, 98, 100 are captured in the openings fixed to the top surface of the platform 92. Then, a part of the opening is shown by a notch 94, and another part is shown by a notch of the notched plate 102.

The plate 90 is bent along the line indicated by the hose 100 and the lower part of this plate 90 lies adjacent the lower part 14. The valve 108 is mounted on the lower portion of the plate 90 and includes an operating member 110. This valve 108
Are three hose connections 112, 114, 116 and hoses 96, 9 connected to these hose connections, respectively.
Has 8,100. These hoses 96, 98, 10
0 is not shown in FIG.

The other end of the hose 96 is connected to one of the discharge valves, and the other end of the hose 98 is connected to the inlet 74.
The other end of 00 is connected to the entrance 76. These connections will be described in detail later in connection with FIG.

Each hose inside the housing 22 is shown in FIG.
Not shown in 3,4.

Referring to FIG. 7, the pneumatic circuit shown is
On the trailer is a quick release gland 118 that connects the pneumatic circuit to the tractor.

Air line 120₁ From ground 118
To the relay valve 122, the air line 120 ₂ Is the relay valve 122
To the air reservoir 124. When the air reservoir 124 is full
Emergency brake is in the “off” position. Air reservoir 1
When 24 is empty, the emergency brake is in the "on" position.

The hose 80 is connected to the circuit 120 ₁ via the T-joint.
Leads to. The hose 80 connects to the air connection 74 and there through the hose 96 to the valve 108. The hose 98 is connected to the pneumatic motor 62 via the valve 68. Air flows from the pneumatic motor 62 to the air valve 70. Each of these valves is connected so that air flows through valve 68 to the pneumatic motor, but is exhausted through valve 70.

Therefore, the effect of applying air pressure to the gland 118 is to rotate the pneumatic motor 62 in the direction of lifting the lower part of the landing leg. Valve 108 at bottom 1
When operated by 6, the air is switched from hose 98 to hose 100 and from there to the air connection 76 and then to the hose 82 leading to the adjusting port of the relay valve 122. The relay valve 122 is opened, and the air is supplied to the air line 120.
₁ and 120 ₂ flow to the air reservoir 124. Thus, the air reservoir 124 is filled and the emergency brake is released.

Another relay valve 126 (FIG. 7) is the housing 2
2 but is shown in FIGS.
Not at all. It has three entrances and exits. One of them
It connects to the hose 84 via the air connection 78 and then to the air
Connect to the reservoir 124. The other hoses 128 and 130
Valve 126 is replaced by valve 70 and air line 120, respectively. ₁ 
Connect to.

When the air reservoir 124 is filled, pressure is applied to the adjusting port of the valve 126 via the hose 130, so that the valve 126 is kept closed. As a result, air does not flow from hose 84 to hose 128 and therefore valve 7
It doesn't flow to zero.

When the release ground 118 is shut off, the pressure in the air line 120 ₁ drops. The control signal for valve 126 is removed, and the valve moves to another position, connecting air reservoir 124 to valve 70, pneumatic motor 62 and valve 68. Air is valve 70 and pneumatic motor 6
2 and is discharged from the valve 68. Pneumatic motor 62
Rotate in the opposite direction and lift the landing leg.

The pneumatic circuit of FIG. 8 also has a number of components found in the pneumatic circuit of FIG. 7, where the same reference numbers are used.

In this system, when the trailer and truck hoses are connected, air flows through the hoses 80 and 96 to the valve 108, and through the valve 108, the rapid relief valve 68.
And is discharged to the atmosphere from the valve 70 through the pneumatic motor 62. The bottom of the landing leg is raised until the bottom 16 moves the valve 108. When valve 108 is moved, air is switched from hose 98 to hoses 100 and 82, which moves relay valve 122. The relay valve 122 opens and air flows along the air lines 120 ₁ and 120 ₂ and then into the brake operating air reservoir 124. A push button operated valve 132 is in the hose and is closed when the air reservoir 124 is filled. Therefore, the air does not flow out of the air reservoir 124 that remains pressurized. Thus the landing legs are raised and the brakes are released.

To lower the landing legs, the air connection between the trailer and the truck is cut off at the gland 118, the relay valve 122 is closed and the air is no longer in the air reservoir 124.
Not supplied to When the push button operating valve 132 is opened, air flows through the valve 70, the pneumatic motor 62 and is released into the atmosphere via the release valve 68.

Thus, the operation of this system is such that each landing leg is automatically raised when the trailer air inlet 118 is connected to the tractor air outlet, but to lower it, a manual pushbutton valve 132 is operated. It is semi-automatic in that it is essential.

[0046]

As described above, the present invention limits the arrangement of the upper and lower parts of the landing leg of the trailer, the pneumatic motor, the air emergency relief valve, and the driving force transmission means for increasing or decreasing the length of the leg. Therefore, there is an effect that it is possible to provide a landing leg that can automatically raise and lower the leg when connecting and disconnecting the trailer and the tractor, and a trailer using the landing leg.

[Brief description of drawings]

FIG. 1 is an external view of an embodiment of a landing leg of the present invention.

FIG. 2 is a top view of FIG. 1 with the housing removed.

3 is a side view of the upper portion of FIGS. 1 and 2. FIG.

FIG. 4 is a side view of the inside of the housing of FIG. 1.

FIG. 5 is a front view of the bracket.

FIG. 6 is an enlarged bottom view of the bracket of FIG.

FIG. 7 is a diagram showing an air circuit system of the landing leg of FIGS. 1 to 6;

FIG. 8 is a diagram showing another air circuit.

[Explanation of symbols]

10 Landing leg 12 Upper part 14 Lower part 16 Bottom part 18 Flange 20,30 ₁ Bolt hole 22,36 Housing 24,90,102 Plate 26 Front member 28 Side member 30,64,72,86 Bracket 32 Bolt 34,88 Bolt center line 38,42 Output shaft 40 Input shaft 44,56,58 Chain wheel 46 Disc 48 Sleeve 48 ₁ Sleeve hole 50,104 Stud 52 Bow nut 54 Chain 60 Chain tensioner 62 Pneumatic motor 66 Air inlet / outlet 68,70 Rapid relief valve 74,76,78 Air connection part 80,82,84,96,98,100,128,13
0 hose 92 platform 94 notch 108 valve 110 operating member 112, 114, 116 hose connection 118 release gland 120 ₁ , 120 ₂ air line 122 relay valve 124 air reservoir 126 second relay valve 132 push-button operation valve

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[Procedure amendment]

[Submission date] December 27, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 1

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction content]

[0007]

According to one aspect of the invention, a landing leg of a trailer has an upper portion having means for mounting the leg on the trailer and is movable relative to the upper portion, thereby allowing the leg to move. A lower portion that increases or decreases in length, a pneumatic motor having first and second inlets and outlets that directly connect the pneumatic motor to the air line so that air flowing in the air line can flow through the motor in either direction, and An air rapid relief valve connected to an air line on one of each side of the motor, each valve having first and second inlets and outlets and an outlet for flowing air into the atmosphere, and An air relief valve connected to keep the air flowing to the pneumatic motor while the valve discharges the air from the pneumatic motor to the atmosphere, and transmits the driving force from the pneumatic motor to the lower part, thereby The lower is displaced vertically relative to the upper, including a driving force transmission means to increase or decrease the length of the legs.

Claims (7)

[Claims] 1. A landing leg for a trailer, wherein the leg has an upper portion having means for mounting the leg on the trailer and is movable relative to the upper portion, thereby increasing or decreasing the length of the leg. A lower portion, and a pneumatic motor having first and second inlets and outlets for directly connecting the pneumatic motor to the air line so that the air flowing through the air line flows in either direction through the motor; An air rapid relief valve connected to the air line on one of the sides of the motor, each valve having first and second inlets and outlets and an outlet for flowing air into the atmosphere; An air rapid relief valve connected to keep the air flowing to the pneumatic motor while each valve discharges air from the pneumatic motor to the atmosphere; And a drive force transmitting means for transmitting a driving force to the lower portion, thereby displacing the lower portion in the upward direction with respect to the upper portion, and increasing or decreasing the length of the leg. 2. An operation member arranged to be engaged when the lower portion is lifted, and a lift from the pneumatic motor is cut off so that the lift of the lower portion is terminated when operated by the lifted lower portion. The landing leg for a trailer of claim 1, including a valve that switches the passage of air. 3. The transmission means is a deceleration transmission means,
A trailing landing leg according to claim 1, whereby rotation of the output shaft of the pneumatic motor slows down rotation of the output shaft of the means. 4. The transmission means comprises a small chain wheel driven by the output shaft of a pneumatic motor, a large chain wheel hung around both wheels and driven by a chain, and driven by the large chain wheel. A trailing landing leg according to claim 3 including a series of gear wheels. 5. The trailer fills when the trailer is coupled with the tractor,
An emergency brake line that connects to an air reservoir for emergency brake operation that becomes empty when the trailer is separated from the tractor, a hose coupling that connects the emergency brake line to the tractor air system, and the upper part that is mounted on the trailer. A landing leg as defined in claim 1, wherein the air line is connected at one end to the emergency brake line and at the other end to the air reservoir for receiving air. 6. A trailer, the landing leg having an upper portion mounted to the trailer and a lower portion movable relative to the upper portion to increase or decrease the length of the landing leg; A pneumatic motor having first and second inlets and outlets connecting the pneumatic motor to the air line for allowing air flowing in either direction through the line to flow through the pneumatic motor; A quick air relief valve, which is connected to the air line by one, each valve including a first and a second
Has an inlet and an outlet for discharging air to the atmosphere, and each valve is connected to keep the air flowing to the pneumatic motor while discharging the air from the pneumatic motor to the atmosphere. An air quick relief valve, a driving force transmission means for transmitting a driving force from the pneumatic motor to the lower portion, thereby vertically displacing the lower portion with respect to the upper portion, and increasing or decreasing the length of the landing leg; An emergency brake line connected to an air reservoir for brake operation, a hose coupling connecting the emergency brake line to the air system of the tractor, and an air inlet, an air outlet and an adjustment port in the brake line, A relay valve in the middle of the ring and the air reservoir, and the lower part is operated so that the lower part is lifted, the emergency brake line and the first emergency relief Air from the pneumatic motor to the relay valve when the relay valve is in the middle of the valve and is operated by lifting the lower portion, thereby opening the relay valve and allowing air to flow to the reservoir. A second relay valve having the relay valve that serves to switch to an adjustment port, and an air inlet, an outlet, and an adjustment port, the adjustment port being connected to the emergency brake line and being a pressure in the emergency brake line. The second relay valve is closed, the air outlet of the second relay valve is connected to a second valve of the exhaust valves, and the air inlet of the second relay valve is the air reservoir. The second pressure drop in the emergency brake line causing the air in the air reservoir to flow to the pneumatic motor when the emergency brake line is disconnected from the tractor. Trailer, including a relay valve, the. 7. The second relay valve is replaced with a manually operated valve that connects between the air reservoir and a second valve of each of the emergency relief valves, thereby operating the manually operated valve. 7. The trailer of claim 6, wherein air is supplied from the air reservoir to the pneumatic motor to lower the landing foot at.