JP3825274B2 - Cab front window device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cab front window device, and more particularly to a cab front window device with improved opening and closing operability.
[0002]
[Prior art]
A typical construction machine, such as a hydraulic excavator, can be freely opened and closed over the entire front window that occupies the front of the cab, which is the cab. The front window is moved between a “closed position” positioned on the front surface of the cab and an “open position” stored on the lower surface of the ceiling. By setting the front window to the “open position” and opening the front of the driver, a wider front view can be provided to the driver. Furthermore, by opening the front window, the inside of the cab can be opened to fresh outside air.
[0003]
To open and close the front window, the driver holds the handle provided on the front window and moves the front window between the “closed position” and “open position” along the guide rail provided on the cab body. Is done. Since the window glass is fitted over the entire front window and is relatively heavy, various improvements have been made to the front window device so that the opening / closing operation can be easily performed.
[0004]
A typical example of an improved front window device is disclosed in Japanese Patent Application Laid-Open No. 11-324019. Referring to FIG. 9 (a figure corresponding to FIG. 9 of the same publication), the front window 50 has a lower roller 52 rotatably attached to both sides of the lower end thereof, and one end of the front window 50 on both sides of the upper end thereof. A stay 54 movably attached and an upper roller 56 pivotally attached to the other end of the stay 54 are provided. The lower roller 52 and the upper roller 56 are moved along a pair of left and right guide rails 60 extending in an L shape from the front side to the ceiling side on both sides of the cab body 58.
[0005]
Although the front window 50 of the above-described front window device is opened and closed by human power, various devices that assist opening and closing have been developed and put into practical use. A typical example is disclosed in, for example, Japanese Patent Application Laid-Open No. 8-209746. The assist device includes a spring device including a spring for lifting the front window on the ceiling of the cab body. Then, the spring device and the front window are connected with a wire, and the front window is pulled in the direction of “open position” by the force of the spring to give a biasing force to assist the opening / closing operation by human power.
[0006]
[Problems to be solved by the invention]
However, the conventional cab front window device having the above-described configuration has the following problems to be solved.
[0007]
(1) Opening and closing operability:
In the front window device disclosed in Japanese Patent Application Laid-Open No. 11-324019 shown in FIG. 9, the upper roller 56 that moves the guide rail 60 is attached to the front window 50 via the stay 54, so The front window 50 can be easily moved along the pair of guide rails 60. However, since the stay 54 can swing freely with respect to the front window 50, if the resistance of the left and right upper rollers 56 is different during the opening and closing process of the front window 50, the positional relationship between the stay 54 and the front window 50. Changes from side to side, and as a result, it becomes difficult to move the front window 50 straight, and the operability of opening and closing becomes worse.
[0008]
(2) Assist device:
If the assist device disclosed in Japanese Patent Application Laid-Open No. 8-209746 is installed on this front window device on one of the left and right sides of the front window, that side is pulled and the front window cannot move straight. If the assist devices are provided on both the left and right sides and applied to both sides, it can theoretically be pulled straight, but in reality, the left and right upper rollers are less likely to be equally left and right due to the difference in the resistance value at each location. Further, although the assist force by the assist device is sufficient on only one side, installing it on the left and right increases the cost of the cab.
[0009]
The present invention has been made in view of the above-described facts, and a technical problem thereof is that a front window including left and right lower rollers and left and right upper rollers attached via a swingable stay is provided with left and right guide rails. It is an object of the present invention to provide a cab front window device having improved operability for opening and closing so that it can be moved up and down straight along.
[0010]
[Means for Solving the Problems]
According to the first aspect of the present invention, a pair of left and right guide rails extending from the front side to the ceiling side on both sides of the cab body, a “closed position” for closing the front surface of the cab along the guide rails, and opening the front surface of the cab. A front window that moves between “open positions” stored on the lower surface of the ceiling, and a lower roller that is rotatably mounted on each of both lower side portions of the front window and that is movable along the guide rail. A stay having one end swingably attached to each of both upper side portions of the front window, and an upper roller rotatably attached to the other end of the stay and movable along the guide rail; A front window device for a cab comprising a stay holding means for applying a restoring force to each of the stays at a predetermined swing position so as to be movable in a clockwise direction and a counterclockwise direction. .
[0011]
The left and right swingable stays are not completely free, but are restrained by giving a return force to the predetermined swinging position so that the left and right of the front window can move substantially the same. To.
[0012]
According to a second aspect of the present invention, in the front window device for a cab according to the first aspect, the stay holding means includes a shaft on which the stay is integrally attached, and the shaft is swingable with respect to the front window. A bracket to be mounted, and a return force applying means for applying a return force to the stay interposed between the bracket and the shaft, and the return force applying means stops the rotation of the shaft and freely moves in the axial direction thereof. A cam member that is fitted, a cam follower that is provided on the shaft and is in contact with the cam member, and a compression spring that is fitted on the shaft that biases the cam member toward the cam follower . Is.
[0013]
And the axis | shaft to which the stay was attached is hold | maintained in the rocking | fluctuation position of a predetermined stay by a return force provision means.
[0015]
Then, a restoring force is applied to the stay by the compression spring, the cam member, and the cam follower.
[0016]
According to a third aspect of the present invention, in the front window device for a cab according to the first or second aspect, the stay is swung against the return force in the “closed position” and “open position” of the front window. By doing so, the front window is positioned at a fixed position where the front window is fixed to the cab body.
[0017]
Then, by applying a force greater than the return force to the stay in the moving operation of the front window and swinging it from the holding position, the front window can be engaged with and fixed to the fixing means at the fixed position.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of a cab front window apparatus constructed according to the present invention will be described in more detail with reference to the accompanying drawings.
[0019]
Referring to FIGS. 1 to 3, the cab front window device includes a pair of left and right guide rails 6, 6 extending in a L shape from the front side to the ceiling side on both sides of the cab body 4, and the guide rails 6, 6. The front window 8 that moves between the “closed position” that closes the front of the cab and the “open position” that opens the front of the cab and is stored on the lower surface of the ceiling, and the lower side of the front window 8 are rotated to A lower roller 10, 10 movably mounted along the guide rails 6, 6, and stays 12, 12 each having one end swingably mounted on each of the upper both sides of the front window 8; The upper rollers 14 and 14 mounted on the other ends of the stays 12 and 12 so as to be rotatable and movable along the guide rails 6 and 6 and the stays 12 and 12 are moved to the predetermined swing positions. Stay holding hand that gives and holds return force And a 16 and 17.
[0020]
The guide rails 6 and 6 are formed in a continuous concave groove shape on the left and right front pillars of the cab body 4 and the inner left and right of the ceiling member. The guide rails 6 and 6 are well known as means for moving the front window. Therefore, the detailed description is abbreviate | omitted.
[0021]
The front window 8 includes a window frame 8a and a window glass 8b bonded to the front surface of the window frame 8a. Opening / closing operation handles 18 are respectively attached by screws 19 at the left and right center of the lower portion of the window frame 8a and the right and left center of the upper portion. A latch 20 for fixing the front window 8 to the cab body 4 at the “closed position” and “open position” is attached to the center of the upper portion by screws 21.
[0022]
The lower rollers 10 and 10 are rotatably attached to brackets 22 and 22 attached by screws 23 to both lower side portions of the window frame 8a. The upper rollers 14 and 14 are rotatably attached to the stays 12 and 12 of the stay holding means 16 and 17 attached by screws 24 to both upper side portions of the window frame 8a.
[0023]
With reference to FIGS. 4-6, the stay holding means 16, 17 and the stay 12 attached thereto will be described in more detail. Since the stay holding means 16 and 17 have a right and left target shape, only one stay holding means 16 will be described.
[0024]
The stay holding means 16 includes a shaft 26 in which the stay 12 is integrally attached at one end, a bracket 28 that swingably attaches the shaft 26 to the window frame 8 a of the front window 8, and a space between the bracket 28 and the shaft 26. And a return force applying means 30 for holding the stay 12 at a predetermined swinging position (position indicated by a solid line in FIG. 4) about the axis 27 and for applying a return force to that position. .
[0025]
The stay 12 is formed by cutting and molding a plate member into a banana shape. One end of the shaft 26 is joined to the end of the shaft 26, and the other end of the roller pin 13 that rotatably holds the upper roller 14 is joined to the surface opposite to the surface to which the shaft 26 is joined.
[0026]
The bracket 28 is formed by molding a plate member, and is provided with two boss portions 28a, 28a formed by winding a plate member that is provided on the axis line 27 at an interval and through which the shaft 26 is rotatably inserted. A mounting surface portion 28b to the window frame 8a and a flange portion 28c for stopping the rotation of a pipe 32 (cam member will be described later) as a cam member are provided.
[0027]
The restoring force applying means 30 is a cam surface F (FIG. 6) that is a cam member that is fitted on the shaft 26 between the boss portions 28a, 28a of the bracket 28 so as to stop rotating and freely move in the direction of the axis 27. , A cylindrical pin 34 that is a cam follower that is screwed into the shaft 26 and protrudes in the radial direction and abuts against the cam surface F of the pipe 32, and the pipe 32 that is fitted on the shaft 26 and faces the pin 26. And a compression spring 36 for biasing.
[0028]
A plate 33 is integrally provided on the outer periphery of the pipe 32. By positioning the plate 33 between the window frame 8a of the front window 8 and the flange portion 28c of the bracket 28, the pipe 32 is centered on the axis 27. The rotation is stopped and the movement in the direction of the axis 27 is possible.
[0029]
The cam surface F engages with the pin 34 at a predetermined position of the stay 12, a position where the roller pin 13 is positioned above the bracket 28 mounting surface of the window frame 8 a, which is indicated by a solid line in FIG. 4 in the present embodiment. It has a semicircular recess 38 (FIG. 6). When the pin 34 is engaged with the recess 38, the pin 34 is held in that position by the force of the compression spring 36. The cam surface F includes inclined surfaces formed on the pipe 32 at an angle α obliquely with respect to the axis 27 on both sides of the recess 38 in the rotation direction about the axis 27.
[0030]
In the stay holding means 16 configured as described above, any force in the swing direction about the shaft 26 is applied to the stay 12, and the force causes the pin 34 and the recess 38 to be engaged by the compression spring 36. When the force exceeds the predetermined force, the pin 34 moves away from the recess 38 and moves along the inclined surface of the cam surface F. The stay 12 swings from the predetermined holding position of the stay 12 (indicated by a solid line in FIG. 4) to an angle θ1 (indicated by a two-dot chain line) in the clockwise direction and an angle θ2 (indicated by a two-dot chain line) in the counterclockwise direction. ) It is movable. The angles θ1 and θ2 are angles at which the stay 12 is swung when the front window 8 is fixed to the cab body 4 in the “closed position” and the “open position” (the fixing of the front window will be described later). .
[0031]
Both the stay holding means 16 and 17 are formed with the same holding position and swing angles θ1 and θ2.
[0032]
With reference to FIG. 7 and FIG. 8 together with FIG. 3, the state of the front window 8 in the “closed position (FIG. 7)”, “open position (FIG. 8)”, and intermediate process (FIG. 3) will be described.
[0033]
As shown in FIG. 3, in the process of opening and closing the front window 8, the stay 12 is held at a predetermined holding position with respect to the front window 8, the state is held, and the front window 8 is moved.
[0034]
In the front window 8 “closed position”, as shown in FIG. 7, the lower roller 10 abuts against a stopper 40 at the end of the guide rail 6, and a latch 20 provided on the front window 8 is a hook provided on the cab body 4. The front window 8 is fixed to the cab body 4 by being engaged with 42. At this time, the stay 12 operates so as not to interfere with the fixing operation by swinging the aforementioned θ1 with respect to the movement of the front window 8 for engaging the latch 20 with the hook 42. When the engagement of the latch 20 and the hook 42 is released, the “closed position” is released and the front window 8 is moved, the stay 12 is moved from the position swung by θ1 to a predetermined holding position (FIG. 3). ) By the action of the stay holding means 16 and 17.
[0035]
In the front window 8 “open position”, as shown in FIG. 8, the upper roller 14 abuts against the stopper 44 at the end of the guide rail 6, and the latch 20 provided in the front window 8 is a hook provided on the cab body 4. 46 and the front window 8 is fixed to the cab body 4. At this time, the stay 12 operates so as not to interfere with the fixing operation by swinging the aforementioned θ2 with respect to the movement of the front window 8 for engaging the latch 20 with the hook 46. When the engagement of the latch 20 and the hook 46 is released, the “open position” is released and the front window 8 is moved, the stay 12 is moved from the position swung by θ2 to a predetermined holding position (FIG. 3). ) By the action of the stay holding means 16 and 17.
[0036]
The operation of the cab front window device as described above will be described.
[0037]
(1) Opening and closing operability:
In the process of opening and closing the front window 8 (FIG. 3), the stay 12 to which the upper roller 14 is attached is held at a predetermined swinging position with respect to the front window 8, so that the left and right upper rollers 14, 14 Even if the resistance is different, the relationship between the stay 12 and the front window 8 does not change on the left and right, and the opening and closing operation of the front window 8 can be performed smoothly. In addition, when the front window 8 and the cab body 4 are fixed and released, the stay 12 can swing from a predetermined holding position (θ1 and θ2 in the above embodiment). Operation is possible.
[0038]
(2) Assist device:
In addition, since the opening / closing operability is improved, the opening / closing operation is easy even without the conventionally used assist device for opening / closing the front window. When equipped with an assist device, even if it is installed only on the left or right side of the front window 8, there is no problem that the front window 8 cannot be moved straight due to the pulling of that side. Can be used. Further, since it is not necessary to install assist devices on both the left and right sides as in the prior art, the problem of an increase in cab cost can be eliminated.
[0039]
As described above, the present invention has been described in detail based on the embodiments. However, the present invention is not limited to the above-described embodiments, and various modifications or corrections may be made within the scope of the present invention, for example, as described below. It is something that can be done.
[0040]
(1) Stay holding position:
In the present embodiment, the holding position of the stay 12 by the stay holding means 16 (17) is positioned above the window frame 8a shown by a solid line in FIG. Depending on the shape, the shape of the guide rail 6, the form of the fixing means, etc., it may be set appropriately according to the form.
[0041]
(2) Swing range of stay:
In the present embodiment, as shown in FIG. 4, the swing range of the stay 12 is set in the range of θ1 and θ2 from the holding position in the clockwise direction and the counterclockwise direction, respectively. The size may be set according to the method and means for fixing the front window to the cab body.
[0042]
(3) Restoring force applying means:
In the present embodiment, the restoring force applying means 30 includes a pipe 32 that is a cam member, a pin 34 that is a cam follower, and a compression spring 36 that biases the pipe 32 toward the pin 34. The return force applying means 30 may be any device that applies a return force to the stay 12 and may not be a cam. Also, the shape of the cam surface of the cam member can be set as appropriate in relation to the restoring force.
[0043]
【The invention's effect】
According to the cab front window device configured according to the present invention, the front window including the left and right lower rollers and the left and right upper rollers attached via the swingable stay is straightened along the left and right guide rails. Thus, it is possible to provide a front window device for a cab with improved opening / closing operability so that it can be moved up and down.
[Brief description of the drawings]
FIG. 1 is a perspective view of a cab having a front window device constructed in accordance with the present invention.
FIG. 2 is an enlarged perspective view showing the main part of the front window device shown in FIG. 1 in an exploded state.
3 is an explanatory view showing the relationship between the front window and the guide rail of the front window device shown in FIG. 1 in a state between the “closed position” and “open position” of the front window.
4 is a side view of the stay holding means shown in the direction of arrow A in FIG.
FIG. 5 is a front view of stay holding means as seen in the direction of arrows BB in FIG. 4;
6A is a side view, FIG. 6B is a front view, and FIG. 6D is a bottom view.
7 is an explanatory view showing the relationship between the front window and the guide rail of the front window device shown in FIG. 1 in a fixed state of the front window “closed position”. FIG.
FIG. 8 is an explanatory diagram showing the relationship between the front window and the guide rail of the front window device shown in FIG. 1 in a fixed state of the front window “open position”.
FIG. 9 is an explanatory diagram of a conventional front window device.
[Explanation of symbols]
4: Cab body 6: Guide rail 8: Front window 10: Lower roller 12: Stay 14: Upper roller 16, 17: Stay holding means 26: Shaft 28: Bracket 30: Restoring force applying means 32: Pipe (cam member)
34: Pin (cam follower)
36: Compression spring 50: Front window 52: Lower roller 54: Stay 56: Upper roller 58: Cab body 60: Guide rail F: Cam surface

Claims (3)

A pair of left and right guide rails extending from the front side to the ceiling side on both sides of the cab body, a `` closed position '' that closes the front of the cab along this guide rail, and an `` open position '' that opens the front of the cab and is stored on the bottom of the ceiling A front window that moves between the lower window, a lower roller that is pivotally mounted on each of the lower sides of the front window and that is movable along the guide rail, and each of the upper sides of the front window. A stay attached to one end of the stay so as to be swingable, an upper roller rotatably attached to the other end of the stay and movable along the guide rail, and the stays at predetermined swing positions. A front window device for a cab, comprising: stay holding means that applies a restoring force and holds it so as to be movable in a clockwise direction and a counterclockwise direction . Stay holding means has a shaft to which the stay is attached integrally, the bracket swings that freely attached only to the shaft to said front window, a return force to the stay is interposed between the bracket and the shaft A restoring force applying means for applying ,
The restoring force applying means includes a cam member that stops rotating on the shaft and is freely fitted in the axial direction thereof, a cam follower that is provided on the shaft and is in contact with the cam member, and the cam member is connected to the cam follower. The cab front window device according to claim 1, further comprising: a compression spring fitted to the shaft that is biased toward the shaft . The front window is positioned at a fixed position where the front window is fixed to the cab body by swinging the stay against the return force in the “closed position” and “open position” of the front window. Or the front window apparatus of the cab of 2 .

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