Patent Publication Number: US-9885170-B2

Title: Cab and work vehicle

Description:
TECHNICAL FIELD 
     The present invention relates to a cab and a work vehicle which includes the cab. 
     BACKGROUND ART 
     In a work vehicle, such as bulldozer and hydraulic excavator, an engine stop switch is provided as a device for stopping operation of the work vehicle promptly. An operator can stop an engine by operating the engine stop switch, without turning off a key switch for switching start and stop of the engine. 
     Conventionally, a work vehicle on which an engine stop switch is provided below an operator&#39;s seat is proposed (for example, refer to PTD 1). 
     CITATION LIST 
     Patent Document 
     
         
         PTD 1: WO2012/060355 
       
    
     SUMMARY OF INVENTION 
     Technical Problem 
     It is necessary to operate the engine stop switch in the emergency. Therefore, it is desirable to place the engine stop switch in a position where the operator sitting on the operator&#39;s seat can operate the engine stop switch promptly. Moreover, it is desirable to install the engine stop switch in an open state rather than to cover the engine stop switch with covering described in PTD 1. On the other hand, since the engine will stop if the engine stop switch is operated accidentally, it is necessary to place the engine stop switch so that an improper operation of the engine stop switch by an unexpected external force may be hard to occur. 
     An object of the present invention is to provide a cab in which an engine stop switch can be caused to make an emergency stop and an improper operation of the engine stop switch can be suppressed, and a work vehicle including the cab. 
     Solution to Problem 
     A cab of the present invention is a cab for a work vehicle and includes an operator&#39;s seat placed in the cab and an engine stop switch for causing an engine to make an emergency stop. The operator&#39;s seat includes a back portion serving as a backrest. The engine stop switch is provided rearward relative to a line which is perpendicular to a midline bisecting the operator&#39;s seat as seen in a plan view and passes the back portion. 
     The cab includes a side rack placed laterally with respect to the operator&#39;s seat in the cab. The side rack includes a first mount portion and a second mount portion mounted with the engine stop switch and adjacent to the first mount portion. An upper surface of the second mount portion is located lower in a upward/downward direction relative to an upper surface of the first mount portion. 
     The cab includes a handled portion handled by an operator sitting on the operator&#39;s seat and provided at the first mount portion. 
     Regarding the cab, three sides of a surrounding of the engine stop switch are exposed. 
     Regarding the cab, a top surface of the engine stop switch is located at or lower in the upward/downward direction than the upper surface of the first mount portion. 
     Regarding the cab, the engine stop switch is a push button switch and, when the engine stop switch is pushed, a top surface of the engine stop switch is located lower in the upward/downward direction than the upper surface of the first mount portion. 
     Regarding the cab, the engine stop switch is a push button switch and, when the engine stop switch is pushed, a top surface of the engine stop switch is located higher in the upward/downward direction than a topmost surface of the second mount portion. 
     Regarding the cab, the second mount portion is adjacent to and located rearward of the first mount portion. 
     Regarding the cab, the upper surface of the second mount portion is mounted only with the engine stop switch. 
     Regarding the cab, the midline tilts with respect to a front-rear direction of the cab, so that the closer the midline is to its frontmost end the further it tilts rightward and the closer the midline is to its rearmost end the further it tilts leftward. The side rack is placed left-rearward of the operator&#39;s seat. 
     A bulldozer of the present invention includes an engine and the above-described cab. 
     Advantageous Effects of Invention 
     According to the present invention, the engine stop switch can be caused to make an emergency stop, and an improper operation of the engine stop switch can be suppressed. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a side view schematically showing the configuration of a bulldozer in the embodiment of the present invention. 
         FIG. 2  is a plan view schematically showing the configuration inside a cab shown in  FIG. 1 . 
         FIG. 3  is an enlarged cross sectional view showing the details of the configuration of a side rack. 
         FIG. 4  is a perspective view of an engine stop switch. 
         FIG. 5  is a cross sectional view of the side rack showing the state where the engine stop switch is operated. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Hereinafter, embodiments of the present invention will be described based on the drawings. 
     First, the configuration of a bulldozer which is an example of a work vehicle to which the idea of the present invention is applicable will be described. 
     In the present embodiment, the forward side (front side) of an operator sitting in a cab  30  is defined as the forward side of a bulldozer  10 , the rear side of the operator sitting therein is defined as the rear side of bulldozer  10 , the left side of the operator in the seated state is defined as the left side of bulldozer  10 , and the right side of the operator in the seated state is defined as the right side of bulldozer  10 . The front-rear direction means the front-rear direction seen from the operator sitting on an operator&#39;s seat of cab  30 . The left/right direction, the vehicle width direction or the lateral direction is the direction of the right and left seen from the above-described operator. In the drawings below, the front-rear direction is shown with an arrow X in the drawings, the left/right direction is shown with an arrow Y in the drawings, and the upward/downward direction is shown with an arrow Z in the drawings. 
       FIG. 1  is a side view schematically showing the configuration of a bulldozer  10  in the embodiment of the present invention. As shown in  FIG. 1 , bulldozer  10  of the present embodiment mainly includes a traveling apparatus, a vehicular body  1 , a blade  2 , and a ripper apparatus  7 . The traveling apparatus has a pair of left and right crawler travel units  3  at a distance in the vehicle width direction (the direction of Y). Vehicular body  1  is placed between the pair of left and right crawler travel units  3 . Blade  2  is placed at the front position of vehicular body  1 . Ripper apparatus  7  is placed at the rear position of vehicular body  1 . 
     Vehicular body  1  has a cab (operator&#39;s cab)  30  and an engine compartment  20 . Cab  30  is placed in the rear upper part of vehicular body  1 . Engine compartment  20  is placed frontward of cab  30 . Engine compartment  20  is placed between cab  30  and blade  2 . An engine  21  is accommodated in engine compartment  20 . Cab  30  is configured so that it may have the operator&#39;s seat inside for the operator to be seated and may surround the operator&#39;s seat. 
     Bulldozer  10  includes blade  2  as a work implement in the front thereof. Blade  2  is the work implement for working the digging of earth and sand, land grading, and the like. Blade  2  has its right and left sides both supported by a frame  4 . Blade  2  is driven by tilt cylinders  5  and lift cylinders  6 . 
     Bulldozer  10  includes ripper apparatus  7  as a work implement in the rear thereof. Ripper apparatus  7  is the work implement for penetrating and crushing the hard material, such as rock. Ripper apparatus  7  has a shank  12 . A ripper tip  11  is provided at the lower end of shank  12 . Ripper apparatus  7  thrusts ripper tip  11  into rock and the like and performs cutting or crushing with the traction by the traveling apparatus. Ripper apparatus  7  is driven by lift cylinders  8  and tilt cylinders  9 . 
       FIG. 2  is a plan view schematically showing the configuration inside cab  30  shown in  FIG. 1 . As shown in  FIG. 2 , an operator&#39;s seat  31  is placed inside cab  30 . Cab  30  has a roof portion which is arranged to cover operator&#39;s seat  31 , and a plurality of pillars which support the roof portion. Each pillar extends along the upward/downward direction (the direction of Z), and is connected with the floor portion and the roof portion of cab  30 . 
     The plurality of pillars have front pillars  51  and  52  and rear pillars  53  and  54 . Front pillars  51  and  52  are placed frontward with respect to operator&#39;s seat  31  in the front-rear direction (the direction of X). Rear pillars  53  and  54  are placed rearward with respect to operator&#39;s seat  31  in the front-rear direction (the direction of X). Front pillar  51  and rear pillar  53  are placed rightward with respect to operator&#39;s seat  31  in the vehicle width direction (the direction of Y). Front pillar  52  and rear pillar  54  are placed leftward with respect to operator&#39;s seat  31  in the vehicle width direction (the direction of Y). 
     Operator&#39;s seat  31  is placed near a substantially center of cab  30 . Operator&#39;s seat  31  has a seating portion  32 , a back portion  33 , and a headrest  34 . The operator who gets into cab  30  is seated on seating portion  32 . In order that the operator who is seated on seating portion  32  may lean the back, back portion  33  is provided. Back portion  33  serves as a backrest. Side supports protruding frontward are provided on a left end and a right end of back portion  33  in order to support the seated operator so that the operator may not be moved. Headrest  34  is attached to the upper end of back portion  33 . Headrest  34  protects the operator&#39;s head from an impact. 
     A front console  46  is placed frontward of operator&#39;s seat  31  in cab  30 . A control panel, meters and switches are attached to front console  46 . 
     A right console  41  is placed rightward of operator&#39;s seat  31  in cab  30 . Levers for operation of the work implement are provided on right console  41 . A blade control lever  42  for operating blade  2  and a ripper control lever  43  for operating ripper apparatus  7  are attached to right console  41 . Blade control lever  42  is placed at the front side of right console  41 . Ripper control lever  43  is placed right-rearward of blade control lever  42 . 
     A right armrest  47  is placed rightward of operator&#39;s seat  31  in cab  30 . Right armrest  47  is placed laterally with respect to operator&#39;s seat  31 . In the vehicle width direction (the direction of Y), right armrest  47  is placed between operator&#39;s seat  31  and right console  41 . Right armrest  47  is placed between ripper control lever  43  and operator&#39;s seat  31 . 
     A left console  44  is placed leftward of operator&#39;s seat  31  in cab  30 . On left console  44 , a lever for travel operation of bulldozer  10  is provided. A travel control lever  45  is attached to left console  44 . Travel control lever  45  is placed at the front side of left console  44 . The rear side of left console  44  is provided as a left armrest. 
     A belt accommodation portion  35  which accommodates a seat belt is placed rightward of operator&#39;s seat  31  in cab  30 . Belt accommodation portion  35  is placed between operator&#39;s seat  31  and right armrest  47 . A locking portion  36  which locks the seat belt is placed leftward of operator&#39;s seat  31  in cab  30 . Locking portion  36  is placed between operator&#39;s seat  31  and left console  44 . The seat belt is pulled out from belt accommodation portion  35 , and a locking metal fitting at a tip of the seat belt is locked to locking portion  36 , thereby the seat belt is worn around the body of the operator sitting on operator&#39;s seat  31 . 
     A side rack  60  is placed leftward of operator&#39;s seat  31  in cab  30 . Side rack  60  is placed laterally with respect to operator&#39;s seat  31 . Side rack  60  is placed left-rearward of operator&#39;s seat  31 . 
     Side rack  60  includes a first mount portion  55  and a second mount portion  61 . A cup holder  56 , an ashtray  57 , a cigarette lighter  58 , and an external connection terminal  59  are provided at first mount portion  55 . Cup holder  56 , ashtray  57 , cigarette lighter  58 , and external connection terminal  59  are collectively placed on first mount portion  55 . Cup holder  56 , ashtray  57 , cigarette lighter  58 , and external connection terminal  59  configure the handled portion handled by the operator sitting on operator&#39;s seat  31 . 
     Second mount portion  61  is placed adjacent to first mount portion  55 . Second mount portion  61  is adjacent to and located rearward of first mount portion  55 . Second mount portion  61  is mounted with an engine stop switch  62 . Engine stop switch  62  is a switch for causing engine  21  ( FIG. 1 ) to make an emergency stop. An upper surface of second mount portion  61  is mounted only with engine stop switch  62 . No devices other than engine stop switch  62  is mounted on the upper surface of second mount portion  61 . 
     An alternate long and short dash line in  FIG. 2  shows a midline ML of operator&#39;s seat  31 . Here, the midline is a virtual line by which operator&#39;s seat  31  is equally divided into right part and left part. In a front view of operator&#39;s seat  31 , midline ML passes along the center of the right and left of operator&#39;s seat  31 . In a rear view of operator&#39;s seat  31 , midline ML passes along the center of the right and left of operator&#39;s seat  31 . As seen in the plan view shown in  FIG. 2 , midline ML passes the center of operator&#39;s seat  31 , and extends in the position which bisects operator&#39;s seat  31 . 
     If operator&#39;s seat  31  has a symmetrical shape, midline ML is on the plane of symmetry. However, operator&#39;s seat  31  of the present embodiment may not be completely symmetrical. Midline ML may be a line which bisects a member with a symmetrical shape which configures a portion of operator&#39;s seat  31 . Midline ML may be a line which bisects a part with a symmetrical shape of a member which configures a portion of operator&#39;s seat  31 . For example, midline ML may be the line which bisects seating portion  32 , may be the line which bisects back portion  33 , or may be the line which bisects headrest  34 . 
     As shown in  FIG. 2 , midline ML of operator&#39;s seat  31  tilts with respect to the front-rear direction (the direction of X) of cab  30 , so that the closer the midline is to its frontmost end the further it tilts rightward and the closer the midline is to its rearmost end the further it tilts leftward. Operator&#39;s seat  31  is fixed at a position that the seated operator faces a direction tilted rightward with respect to front direction in the front-rear direction of the bulldozer as seen in the plan view. 
     The chain double-dashed line in  FIG. 2  shows a perpendicular line PL perpendicular to midline ML as seen in the plan view and passing back portion  33  of operator&#39;s seat  31 . 
       FIG. 3  is an enlarged cross sectional view showing the details of the configuration of side rack  60 . In  FIG. 3 , cup holder  56 , ashtray  57 , and cigarette lighter  58  provided on first mount portion  55  are illustrated. In  FIG. 3 , in addition, engine stop switch  62  provided on second mount portion  61  is illustrated. Second mount portion  61  is provided substantially rearward relative to perpendicular line PL as seen in the plan view. Engine stop switch  62  is provided rearward relative to perpendicular line PL as seen in the plan view. In  FIG. 2 , perpendicular line PL passes the rearmost portion of a front surface  33   a  of the back portion. Perpendicular line PL is not restricted to the position shown with  FIG. 2 , and may pass an arbitrary portion of back portion  33 , for example, the rearmost portion of back portion  33 . 
     A line L 1  shown with the chain double-dashed line in  FIG. 3  shows the position of an upper surface of first mount portion  55 . A line L 2  shown with the chain double-dashed line in  FIG. 3  shows the position of the upper surface of second mount portion  61 . As shown in  FIG. 3 , the upper surface of second mount portion  61  is located lower in the upward/downward direction relative to the upper surface of first mount portion  55 . Between the upper surface of first mount portion  55  and the upper surface of second mount portion  61 , a level difference of height H shown in  FIG. 3  is formed. 
     Engine stop switch  62  is a push button switch. Switching operation of the switch is performed by pushing engine stop switch  62  with a hand. The position of a top surface of engine stop switch  62  in the upward/downward direction is the same as the upper surface of first mount portion  55 . The position of a top surface of engine stop switch  62  in the upward/downward direction may be lower than the upper surface of first mount portion  55 . The top surface of engine stop switch  62  is located at or lower in the upward/downward direction than the upper surface of first mount portion  55 . 
     A wall portion  63  which connects the upper surface of first mount portion  55  and the upper surface of second mount portion  61  is provided at the rear end of first mount portion  55  and at the front end of second mount portion  61 . Engine stop switch  62  faces wall portion  63 . 
       FIG. 4  is a perspective view of engine stop switch  62 . As shown in  FIG. 4 , the upper surface of second mount portion  61  is mounted only with engine stop switch  62 . No member or device is provided around engine stop switch  62  other than wall portion  63  which connects first mount portion  55  and second mount portion  61 . 
     Second mount portion  61  in the present embodiment has a flat surface, however, second mount portion may have a curve or protrusion so long as it does not hinder the operation of engine stop switch  62 . 
     Wall portion  63  is provided on one side of a surrounding of engine stop switch  62 , and the other three sides of the surrounding of engine stop switch  62  are exposed. Wall portion  63  is provided frontward of engine stop switch  62 . No wall portion is provided rightward, leftward and rearward of engine stop switch  62 . Engine stop switch  62  is placed so that three sides of right side, left side and rear side of engine stop switch are exposed. In the three sides of right side, left side and rear side relative to engine stop switch  62 , any structure or device which may hinder the operation of engine stop switch  62  is not provided. 
       FIG. 5  is a cross sectional view of the side rack  60  showing the state where the engine stop switch  62  is operated. Engine stop switch  62  is the push button switch, and the state where engine stop switch  62  is pushed and move downward is illustrated in  FIG. 5 . 
     As shown in  FIG. 5 , when engine stop switch  62  is pushed, the top surface of engine stop switch  62  is located lower in the upward/downward direction than the upper surface of first mount portion  55 . The top surface of engine stop switch  62  is placed in the position lower than line L 1  which shows the position of the upper surface of first mount portion  55 . When engine stop switch  62  is pushed, the top surface of engine stop switch  62  is placed in the region between line L 1  which shows the position of the upper surface of first mount portion  55  and line L 2  which shows the position of the upper surface of second mount portion  61 . 
     When engine stop switch  62  is pushed, the top surface of engine stop switch  62  is located higher in the upward/downward direction than the upper surface of second mount portion  61 . If second mount portion  61  has unevenness, the top surface of engine stop switch  62  is located higher in the upward/downward direction than the topmost surface of second mount portion  61 . 
     Next, the function and effect of the present embodiment is explained. 
     Cab  30  of the present embodiment includes operator&#39;s seat  31  and side rack  60 , as shown in  FIG. 2 . Side rack  60  is placed leftward in the vehicle width direction (the direction of Y) with respect to operator&#39;s seat  31 . 
     Side rack  60  has first mount portion  55 . Cup holder  56 , ashtray  57 , cigarette lighter  58 , and external connection terminal  59  are provided at first mount portion  55 . Cup holder  56 , ashtray  57 , cigarette lighter  58 , and external connection terminal  59  configure the handled portion handled by the operator sitting on operator&#39;s seat  31 . 
     Side rack  60  has second mount portion  61 . Second mount portion  61  is mounted with engine stop switch  62  for causing engine  21  to make an emergency stop. Second mount portion  61  is adjacent to first mount portion  55 . 
     As shown in  FIG. 3 , the upper surface of second mount portion  61  is located lower in the upward/downward direction relative to the upper surface of first mount portion  55 . As shown in  FIG. 4 , three sides of the surrounding of engine stop switch  62  are exposed. 
     Since engine stop switch  62  is placed on side rack  60 , the operator sitting on operator&#39;s seat  31  can reach out to second mount portion  61  and can operate engine stop switch  62 . Frontward of engine stop switch  62  wall portion  63  is provided, but the other three sides of the surrounding of engine stop switch  62  are exposed without being provided with a wall. There is no covering which covers engine stop switch  62 , and engine stop switch  62  is exposed. When the operator tries to operate engine stop switch  62  in the emergency, the operator&#39;s operation is not hindered by the structure around engine stop switch  62 . Therefore, the operator can operate engine stop switch  62  promptly and cause engine  21  to make an emergency stop. 
     Second mount portion  61  is provided with engine stop switch  62 . Second mount portion  61  is placed in the position different from first mount portion  55  at which the handled portion handled by the operator is provided. Thereby, an accidental contact with engine stop switch  62  by the operator when the operator handles the handled portion can be restrained. Since the upper surface of second mount portion  61  is located lower than the upper surface of first mount portion  55 , an unintentional contact with engine stop switch  62  can be more reliably avoided. Therefore, an improper operation of engine stop switch  62  can be suppressed. 
     As shown in  FIG. 3 , the top surface of engine stop switch  62  is located at or lower in the upward/downward direction than the upper surface of first mount portion  55 . Thereby, an accidental contact with engine stop switch  62  by the operator when the operator handles the handled portion can be restrained, and an improper operation of engine stop switch  62  can be suppressed. 
     As shown in  FIG. 5 , engine stop switch  62  is a push button switch, and the top surface of engine stop switch  62  when engine stop switch  62  is pushed is located lower in the upward/downward direction than the upper surface of first mount portion  55 . Thereby, an accidental contact with engine stop switch  62  by the operator when the operator handles the handled portion can be restrained, and an improper operation of engine stop switch  62  can be suppressed. 
     As shown in  FIG. 2 , second mount portion  61  is adjacent to and located rearward of first mount portion  55 . In side rack  60 , by providing first mount portion  55  frontward and providing second mount portion  61  rearward, an unintentional contact with engine stop switch  62  by the operator when the operator handles the handled portion can be restrained. Therefore, an improper operation of engine stop switch  62  can be suppressed. 
     As shown in  FIGS. 2 and 4 , the upper surface of second mount portion  61  is mounted only with engine stop switch  62 . Thereby, an unintentional contact with engine stop switch  62  can be restrained when the operator operates other devices or handles other member. Therefore, an improper operation of engine stop switch  62  can be suppressed. 
     As shown in  FIG. 2 , midline ML bisecting operator&#39;s seat  31  as seen in the plan view tilts with respect to the front-rear direction of cab  30 , so that the closer the midline is to its frontmost end the further it tilts rightward and the closer the midline is to its rearmost end the further it tilts leftward. Side rack  60  is placed left-rearward of operator&#39;s seat  31 . By placing side rack  60  in the position farther away from the operator sitting on operator&#39;s seat  31 , an accidental contact with engine stop switch  62  by the operator can be restrained, and an improper operation of engine stop switch  62  can be suppressed. On the other hand, side rack  60  is placed in the position which the operator can reach by rotating the body. Therefore, in the emergency, the operator can rotate the body and operate engine stop switch  62 . 
     The work vehicle of the present embodiment includes engine  21  and one of the above-mentioned cab  30 . The operator sitting in cab  30  can operate engine stop switch  62  to cause engine  21  to make an emergency stop. In addition, an improper operation of engine stop switch  62  can be suppressed. 
     In cab  30  described above, as shown in  FIG. 4 , the periphery of second mount portion  61  on which engine stop switch  62  is provided extends, except for wall portion  63 , downward with respect to the upper surface of second mount portion  61 . The cab is not restricted to this configuration. A structure which protrudes slightly upward from the upper surface of second mount portion  61  may be provided in the three sides of a surrounding of second mount portion  61  except wall portion  63 . However, in order not to hinder the emergent operation of engine stop switch  62 , it is necessary to expose three sides of the surrounding of engine stop switch  62 . Therefore, the height at which the structure protrudes from the upper surface of second mount portion  61  is defined so that it may become smaller than the distance from the upper surface of second mount portion  61  to the movable portion of engine stop switch  62 . 
     Engine stop switch  62  is not restricted to the push button switch described above, but may be an arbitrary kind of switch such as a toggle switch. However, a push button switch which is switched between ON and OFF by pushing the button is suitable as engine stop switch  62  due to the characteristic of engine stop switch  62  that the emergent operation is required. 
     It should be construed that the embodiments disclosed herein are given by way of illustration in all respects, not by way of limitation. It is intended that the scope of the present invention is defined by claims, not by the description above, and encompasses all modifications and variations equivalent in meaning and scope to the claims. 
     REFERENCE SIGNS LIST 
     
         
         
           
               1  vehicular body;  2  blade;  7  ripper apparatus;  10  bulldozer;  21  engine;  30  cab;  31  operator&#39;s seat;  33  back portion;  33   a  front surface of the back portion;  41  right console;  42  blade control lever;  43  ripper control lever;  44  left console;  45  travel control lever;  46  front console;  47  right armrest;  55  first mount portion;  56  cup holder;  57  ashtray;  58  cigarette lighter;  59  external connection terminal;  60  side rack;  61  second mount portion and;  62  engine stop switch;  63  wall portion; ML midline; PL perpendicular line.