Adjustable seat for an industrial vehicle

A support assembly for the seat (32) of an electric lift truck (10) which permits the seat to be pivoted about a vertical support member (24) and slid outward to move the seat clear of the truck's battery compartment (12). The means for pivoting the seat includes a first latch (44) which normally keeps the seat from rotating relative to the support member (24). The seat is mounted on a sliding mounting assembly (30) which allows the seat to be slid outward of the truck, and which also includes a latch assembly (68) for normally maintaining the seat in an operating position.

This invention relates to seats for industrial vehicles, and more 
particularly to an adjustable seat particularly adapted for use in an 
electric lift truck. 
In an electric lift truck, an operator's station is normally provided 
adjacent the forward end of the truck, and a battery is located adjacent 
the rear end of the truck. The operator's seat is generally located above 
at least a portion of the compartment which houses the battery; therefore, 
when the battery is to be removed, it is necessary for the seat to be 
moved to a non-interfering location, either by removing the seat, or by 
means which permit the seat to be moved temporarily by pivoting or 
otherwise. 
In some lift truck designs, it is sufficient to pivot the seat forward to 
provide access to the battery. On others, the seat can be pivoted to the 
side or about multiple axes. 
Another factor which must be considered in the design of such adjustable 
seats is the nature of the equipment which is used to remove the battery. 
In order to accommodate certain types of overhead battery removal 
equipment, it is necessary to move the seat to a position outside the 
boundary defined by the vehicle, a position which is difficult to attain 
by simple pivot means. 
It is thus an object of the present invention to provide a seat for a lift 
truck which can be moved to a position outside the boundary of the vehicle 
while leaving the seat attached to the vehicle. 
Another object of the invention is to provide a seat as above which 
incorporates adjustment means which is simple, reliable, and inexpensive. 
To meet the above objectives, the present invention provides a mounting 
assembly for a vehicle seat which allows the seat to be pivoted to a side 
of the vehicle and then slid outward away from the vehicle. A first latch 
is provided at the pivot point, which is both simple to operate and yet 
positively locks the seat in position for operation of the vehicle. A 
second latch normally maintains the seat in an operating position and 
permits outward sliding of the seat when a release mechanism is actuated.

Referring to the drawings, there is illustrated an electric lift truck 10, 
including a frame 11, a battery compartment 12, and an operator's station 
14. 
The operator's station comprises the well-known controls normally 
associated with a lift truck, including a steering wheel 16, lift control 
18, tilt control 19, auxiliary control 20; and a seat assembly 22. 
The seat assembly 22 is mounted on a primary support member 24, which is 
pivotally mounted internally of the frame 11 and which is spring biased to 
tilt to the right when unoccupied as viewed in FIG. 1, to define a dead 
man control. Such controls are well-known in the art, comprising switch or 
linkage means operatively connected to the support member 24 to render the 
truck inoperative when the operator leaves the seat, and will not be 
described in further detail herein. 
Referring particularly to FIGS. 3, 4 and 5, the seat assembly 22 comprises 
a substantially L-shaped seat support member 26 which is pivotally 
received in a support block 28 welded or otherwise fastened to the free 
end of the primary support member 24, a seat mounting assembly 30 
slidingly received on the support member 26, and a seat 32 bolted or 
otherwise fastened to the support assembly 30. 
To mount the seat support member 26 to the primary support member 24, a 
hole 34 is formed in the upper surface of support block 28 to receive a 
pin 36 which is welded to the short leg of the support member 26. 
To retain the seat support member 26 in an aligned position relative to the 
primary support member 24, a latch plate 44 is slidably attached to the 
front face 46 of the seat support member 26. The latch plate 44 is 
L-shaped in profile, with the short leg defining a handle. Slots 50 are 
formed in the long leg, and shouldered screws 52 are loosely received 
through the slots and threaded into the support member 26, where they are 
locked by means of nuts 54. 
When the pin 36 is received in hole 34, with the lower end of the support 
member 26 resting against the upper surface of the support block 28, and 
the latch plate 44 is in its lowermost position as shown in full line in 
FIG. 4, the latch plate acting against support block 28 prevents the seat 
support member 26 from pivoting relative to primary support member 24, 
thus retaining the seat assembly in its normal angular position as shown 
in FIG. 1 and in full line position of FIG. 2. When it is desired to swing 
the seat assembly 22 clear of the battery compartment 12, the latch plate 
44 is lifted, as shown by the broken line position of FIG. 4, until its 
lower edge is aligned with the lower edge of the seat support member 26, 
allowing the support member 26 to be pivoted relative to the primary 
support member 24 on pin 36. 
To move the seat 32 completely clear of the truck, the seat mounting 
assembly 30 is adapted to slide outward relative to the seat support 
member 26. The seat mounting assembly 30 comprises a relatively thin plate 
56 to which a pair of elongated runners 58 are welded, and a pair of seat 
support crossmembers 60 which are welded to the undersides of the runners 
58 at opposite ends thereof and oriented perpindicularly thereto. The seat 
32 includes a lower frame member 33 having feet 35 attached thereto which 
are bolted to the crossmembers 60 by means of bolts 62. 
The seat mounting assembly 30 is received on the long leg of the support 
member 26 by sliding it over the leg, with the plate 56 received on top of 
the support member 26 and the crossmembers 60 beneath the leg. The runners 
58 are spaced apart on the plate 56 to provide a sliding fit against the 
side edges of the support member 26. An elongated slot 64 is formed 
through the plate 56 along its longitudinal centerline. Sliding movement 
of the seat mounting assembly 30 relative to the support member 26 is 
limited by means of a pin 66 which is press fit into the support member 26 
at assembly and extends upward into the slot 64. 
In FIGS. 3 and 4 the seat mounting assembly is illustrated in its normal, 
or forward position relative to support member 26, with the pin 66 in 
contact with the right end (as viewed in FIGS. 3 and 4) of the slot 64. To 
move the seat 32 clear of the truck 10, the seat mounting assembly 30 can 
be slid to the right relative to the support member 26 until the pin 66 
contacts the left end of slot 64, as illustrated by the broken line 
position of FIG. 2. 
To maintain the seat in its forward position for normal truck operation, a 
latch assembly 68 is provided, acting between the seat support member 26 
and the seat mounting assembly 30. Referring particularly to FIGS. 3, 4 
and 6, the latch assembly comprises a cylindrical latch member 70 which is 
received in a hole 72 formed in the seat support member 26 and retained 
therein by a flat spring 74 which is riveted or otherwise fastened to the 
underside of the latch member and to the underside of the seat support 
member 26 by screws or the like. The top surface 71 of latch member 70 is 
angled downward from front to back (left to right as shown in FIG. 6) and 
the height at the front is slightly greater than the thickness of the 
support member 26, so that the front edge of the latch member engages a 
keyhole slot 76 formed in the plate 56. To facilitate disengagement of the 
latch assembly, a pin 78 is press fit into an axial hole formed in the 
latch member 70, and a cylindrical knob 80 is press fit onto the pin. In 
its normal position, as shown in FIG. 4, the spring 74 maintains the latch 
member in a position wherein the top front edge of the latch member 
engages the plate 56. When it is desired to move the seat 32 outward on 
the support member 26, the knob 80 is pushed downward against the pressure 
of spring 74 until the latch member 70 clears the plate 56. The plate 56, 
to which the seat 32 is attached through runners 58 and crossmembers 60, 
is then slid to the right as viewed in FIG. 4 until the pin 66 contacts 
the front edge of slot 64. When it is desired to return the seat to its 
normal position, the plate 56 is slid to the left as viewed in FIG. 4. 
Because of the angle of the top surface 71 of latch member 70, the plate 
56 will force the latch member downward against the force of spring 74, 
until the latch member registers with the circular portion of keyhole slot 
76, and re-engages the plate. A resilient bumper 81 is adhered to a 
downturned portion 82 of the plate 56, and engages the rear edge of the 
seat support member 26 when the pin 66 engages the right end of slot 64. 
The bumper cushions the engagement of the pin with the end of the slot, 
and the resiliency of the bumper causes the plate 56 to be biased slightly 
to the right, thus insuring that the latch member 20 will be maintained in 
a locked position against the edge of keyhole slot 76. 
When the truck 10 is ready for operation, the seat assembly 22 will be in 
the position shown in FIG. 1, with the seat support member 26 in its 
latched position with respect to primary support member 24, and the seat 
32 in its latched position with respect to the seat support member 26. 
When it is desired to gain access to the battery compartment 12 for removal 
or servicing of the truck's batteries, the latch plate 44 is raised to the 
broken line position of FIG. 4 to allow the seat support member 26 to be 
rotated. The latch assembly 68 is then actuated by pushing down on knob 
80, and the plate 56 is slid outward, thus putting the seat in the broken 
line position of FIG. 2.