JPH0116716B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cab-lifting device for a cab-over type vehicle, which is required when the engine room of the vehicle is inspected or repaired.

In cab-over type automobiles, the driver's cab is provided above the engine room, so the driver's cab must be lifted up when inspecting or repairing the engine room.

Therefore, one of the conventional cab lifting devices is to use a hydraulic cylinder.
In the case of this method, when the driver's cab is set to a normal state and the vehicle is in a running state, the hydraulic cylinder directly receives vertical vibrations in the driver's cab, which deteriorates the ride comfort of the vehicle. You will end up letting it happen.

To solve this problem, so-called lost motion (lost motion) has traditionally been applied to the hydraulic cylinder.
However, this configuration is complicated and expensive.

On the other hand, there is a system that mechanically disconnects the driver's cab from the hydraulic cylinder to perform the lost motion, but the idea behind these conventional mechanical methods is that when the hydraulic actuator lifts the driver's cab, Alternatively, no consideration is given to a mechanism for escaping the lateral shaking of the driver's cab when the vehicle is running. As a result, if the lifting is carried out according to the conventional concept that does not take such escape measures,
Problems arise, such as the lifting device being damaged or having poor durability.

An object of the present invention is to provide a driver's cab lifting device that improves the above-mentioned problems.

To explain the present invention based on an embodiment, Fig. 1 shows a side view of a driver's cab lifting device as an embodiment of the present invention when it is attached to an automobile. Fig. 2 shows a cross-sectional view of the support 3 in Fig. 1, and Fig. 3 shows a cross-sectional view of Rollo in Fig. 2. , piston rod (hereinafter referred to simply as rod)
5 indicates the state in which the hydraulic actuator 4 is most retracted.

As shown in FIG. 1, the cab lifting device according to the present invention is composed of a hydraulic actuator 4, a rod 5 in the hydraulic actuator 4, a support 3, and a switching valve for operating the hydraulic actuator 4. In FIG. 1, illustration of the switching valve is omitted for convenience of explanation.

In the embodiment shown in FIG. 1, the axial end 4a of the hydraulic actuator is pivotally connected to the chassis 2 of the automobile, and the support 3 is fixed to the driver's cab 1. In such a configuration, the rod 5 When the driver's cab 1 is extended upward, the driver's cab 1 can be tilted around a fulcrum pivoted in front of the chassis 2, as shown in FIG.

As shown in FIGS. 2 and 3, the structure of the support 3 is such that bearing materials 3m and 3n are fitted into holes 3j and 3k formed on both sides of the support 3, respectively. The rotor 3 is made rotatable in the holes 3s and 3t, which are formed in each of the holes 3n, so that the rotor 3 can rotate and slide around the axial center of the hole.
The holes 3s and 3t are perpendicular to the sides of the cab 1, and the rotor 3a has a hole 3p perpendicular to the axis of the holes 3s and 3t. A bearing material 3r is fitted into the perforation 3p, and a concave spherical bearing surface 3c is cut into the bearing material 3r.
A member 3b forming a convex spherical bearing surface 3i
The rod 5 is fitted into a hole 3d drilled in the member 3b such that it can be slid in the axial direction of the rotor 3a. , rails 3e, 3e having a concave spherical rail surface shape are fixed on both sides of a space 3f in which the rod 5 rotates and oscillates together with the rotor 3a, and the center of the concave spherical surface is located at the center of the rotation of the rotor 3a. It coincides with the intersection 3h between the center and the axial center of the perforation 3d.

A contact member 5a is screwed onto the rod 5 in a symmetrical shape in the outer circumferential direction of the rod 5 and has a brim-like shape, and the back surface 5b of the contact member 5a has a convex spherical shape. The radius of curvature of the spherical surface is the same as that of the above-mentioned spherical surface formed on the surfaces of the rails 3e, 3e.

To explain its function in the above configuration, in the state shown in Fig. 2, that is, in the state in which the rod 5 is retracted the shortest possible time, the driver's cab has returned to the position where the car is ready to be driven. In this state, when the car is driven, the driver's cab 1 generally vibrates relative to the chassis 2, but in this case, the support 3 fixed to the driver's cab 1 vibrates.
This enables a lost motion in which the rod 5 can freely vibrate vertically in the portion of the perforation 3d, and the riding comfort caused by the vibration is reduced by an independent shock absorber structure (not shown). The device can dampen the vibrations for comfort.

When inspecting or repairing the engine, etc. located at the bottom of the driver's cab 1 from the above-mentioned normal driving position, when the hydraulic actuator 4 is operated and the rod 5 is extended, the front surface 5 of the abutment member 5a
c eventually comes into contact with the side edge 3g, and as the rod 5 further extends, the rod 5 touches the abutment material 5.
a, the driver's cab 1 is lifted up as shown in FIG. 1 via the rotor 3a, bearing members 3m, 3n, and support 3.

In this way, in the process of the rod 5 lifting the driver's cab 1, the center of gravity of the driver's cab 1 rotates counterclockwise around the pivot point on which the driver's cab 1 is tilted. From the initial start of operation until the center of gravity is on the vertical line of the pivot center, the weight of the driver's cab 1 is supported by the rods 5 and pushed up.

On the other hand, when the center of gravity passes over the vertical line passing through the pivot center and moves to the left of the vertical line (Fig. 1), the cab 1 moves further counterclockwise due to its own weight. Since the driver's cab 1 will try to turn in the circumferential direction, the rod 5 must be designed to support the movement of the driver's cab 1 in a tensile manner after entering this state.

Hereinafter, the operation of the process from just before the center of gravity of the driver's cab 1 passes through the vertical line will be explained.

When the driver's cab 1 is tilted counterclockwise from the state shown in FIG. rotate clockwise. In this case, the rotation in the clockwise direction firstly causes the rod 5, together with the member 3b, to rotate relative to the rotor 3a with respect to the bearing surface 3c.
The rod 5 rotates counterclockwise on the paper surface of FIG. 3 about the intersection 3h, and eventually due to this rotation, the rod 5 comes into contact with the wall surface of the perforation 3u, which serves as a stopper, and after the corresponding contact. The rotation of rod 5
The rotor 3a and the rotor 3a work together to rotate counterclockwise around the rotation axis of the rotor 3a, and in this action, the front surface 5c of the abutting member 5a has already turned to the side surface as described above. In this state, the male spherical surface of the back surface 5b is kept in contact with the end portion 3g, and in this state, as described above, the male spherical surface of the back surface 5b is , while sliding onto the rails 3e, 3e, the contact member 5a further rotates clockwise in FIG. 3 around the intersection 3h, and as the rod 5 further extends from this state, as described above,
Since the weight of the driver's cab acts in the direction of pulling the rod 5, when this state is entered, the rails 3e, 3e fixed to the driver's cab 1 are pressed against the back surface 5b by the gravity, As a result, the driving cab 1 is tilted to a predetermined position while the pressing force is supported by the hydraulic actuator 4 via the abutting member 5a and the rod 5.

As described above, in the operation of lifting the cab, the cab lifting device of the present invention is such that the rod 5 can freely rotate around the axial center of the rod 5, but the abutment member 5a is Since the back surface 5b is formed symmetrically in the outer radial circumferential direction of the rod 5, even when the rod 5 rotates about the axis, the shape of the back surface 5b relative to the rails 3e, 3e is always the same. As a result, even if the rod 5 is not provided with a complicated device such as a rotation stopper around the center of the shaft, the back surface 5b can always slide onto the rails 3e and 3e when in a required position. It is possible.

Also, as can be understood from the above explanation of the action,
In the driver's cab lifting device according to the present invention, since the back surface 5b and the receiving surface 3e have a mutually spherical shape, the mutual contact during the sliding motion is a surface contact, and as a result, the surface pressure during the contact is extremely reduced. This has the advantage of making it possible to easily select the material for the contact material 5a and/or the receiving surface 3e, and also reduces the surface pressure of the contact by using an appropriate bearing material or the like. Therefore, it is also possible to reduce the frictional force in the contact.

Furthermore, in the above description, rails 3e, 3e
The configuration in which the rotor 3a and the back surface 5b are in contact with each other to support the weight of the cab is one in which a contact member 5a is provided between the rotor 3a and the hydraulic actuator 4, and the contact member 5a is shown in FIG. , it is provided on the tip end side of the rod 5 on the upper side of the rotor 3a, and on the rail 3
e and 3e may be provided in a portion indicated by a virtual line 3q in FIG. 3. However, it will be easily understood that in this case, the spherical surface of the back surface 5b of the abutment member 5a is a concave spherical surface, and the rail 3q must have a convex spherical shape.

In the above action, as a practical matter, between the rod 5 and the support 3, as the driver's cab 1 is tilted, the rod 5 moves relative to the support 3 within the plane of FIG. The rod 5 must be able to swing relative to the support 3 to some extent not only in the relative clockwise direction, but also in the direction perpendicular to the plane of the paper in FIG. It consists of a hydraulic actuator 4 and a support 3.
This is because it is necessary to take into account the relative installation error between the driver's cab 1 and the horizontal shaking of the driver's cab 1 when the driver's cab 1 is tilted by the hydraulic actuator 4 or when the vehicle is traveling.

Regarding this problem, in the present invention, member 3b
Since the rod 5 has a spherical shape and the bearing surface 3c supports the member 3b, the relative movement of the rod 5 with respect to the support 3 can be performed at the same time as the above-mentioned rotation horizontal to the plane of the paper in FIG. , during the relative movement between the support 3 and the rod 5 when lifting the driver's cab 1 or when the vehicle is traveling, by allowing free rocking other than horizontally. is designed so that it does not cause any unreasonable movement.

Here, in the above embodiment, if the spherical bearing surface 3i of the member 3b is configured to be directly supported by the support 3, then the back surface 5b will rotate and swing as it slides on the rails 3e, 3e. Also for
In addition, the above-mentioned vibrations, etc., can cause the rotor 3a to pivot in any direction, but in the configuration of the present invention, the support 3 supports the rotor 3a. Furthermore, the reason why the rotor 3a is configured to pivotally support the member 3b is as follows.

That is, in the configurations shown in FIGS. 2 and 3, oil seals or dust seals are not provided on the spherical bearing surfaces 3c and 3i, but depending on the practical usage conditions, it is necessary to provide these seals. However, in this case, since the seal between the spherical surfaces has a spherical shape in which the relative sliding between the bearing surface 3c and the bearing surface 3i is spherical, it may be difficult to increase the oscillation.

As a result, in the embodiments shown in FIGS. 2 and 3, the above-described configuration is adopted in order to deal with the case where the above-mentioned seal is required, and the back surface 5b of the contact member 5a slides onto the rails 3e, 3e. The rotation of the rod 5 is borne by the rotation of the rotor 3a, and the rotation of the rod 5 is borne by the rotation of the rotor 3a. This is what is being done.

In the above action, the end 4a of the hydraulic actuator 4 is pivotally connected to the chassis 2, but conversely, the end 4a is pivotally connected to the driver's cab 1 side, and the support 3
It will be easily understood from the above description that it may be fixedly attached to the chassis 2 side.

As is clear from the above description, in the driver's cab lifting device of the present invention, the support 3 pivotally supports the rotor 3a, the rotor 3a further pivotally supports the member 3b, and the rod 5 is attached to the member 3b. By providing the perforation 3d for sliding guidance and by fixing the abutment member 5a on the rod 5 for pushing up the rotor 3a, when the driver's cab is in the position where the car is ready to travel, the rod 5
Allowing lost motion between and the support 3,
In addition, the vibration between the driver's cab and the rod due to the traveling is also allowed, and when the hydraulic actuator 4 lifts the driver's cab 1, the support 3 and the hydraulic actuator 4
The support 3, the rod 5, or the hydraulic actuator 4 will not be damaged or their durability will not be deteriorated due to a relative installation error with the driver or the horizontal shaking of the driver's cab 1 during lifting. The driver's cab 1 can be lifted smoothly.

In addition, the cab lifting device of the present invention can be configured such that the sealing material used in the spherical bearing portion of the member 3b has good durability, and the member 3b has only a small swing angle. Since it is only necessary to bear the oscillation of the spherical bearing, there is no need to form the spherical bearing with such high accuracy, and the member 3b can be housed in a small size.

[Brief explanation of drawings]

FIG. 1 shows a side view of a driver's cab lifting device as an embodiment of the present invention when it is attached to an automobile, and FIG. 2 shows a supporting device 3 in FIG. 1.
FIG. 3 shows a cross-sectional view taken along the Rollo line in FIG. 2. The symbols used in the examples are as follows. 1: Cab, 2: Chassis, 3: Support, 3
a: rotor, 3b: member, 3c and 3i: bearing surface, 3d, 3j, 3k, 3p, 3s, 3t and 3u: perforation, 3e and 3q: rail, 3f: space, 3g: side edge, 3h: Intersection, 3m, 3n and 3r: bearing material. 4: Hydraulic actuator, 4
a: End. 5: Piston rod, 5a: Contact material,
5b: Back, 5c: Front.

Claims (1)

[Claims] 1. An end portion 4a of a hydraulic actuator 4 is pivotally connected to either the driver's cab 1 or the chassis 2, and a support 3 is fixed to the other of the chassis or the driver's cab. However, in the support device, a perforation 3 is formed in a direction perpendicular to the side of the driver's cab.
s and 3t are drilled, and the rotor 3a is rotatably slidable around the axial center of the drilled hole.
The rotor is fitted with a member 3 having a spherical outer shape.
b is pivotally supported, another borehole 3d is bored in the member, and the piston rod 5 of the hydraulic actuator is fitted into the other borehole so as to be able to slide in the axial direction of the other borehole. However, when the piston rod lifts the driver's cab, the abutting material 5a that performs the lifting is fixed to the rotor by abutting against the side end 3g of the rotor. is characterized in that when the piston rod rotates and oscillates relative to the rotor around the axis of the borehole, the piston rod is provided with a stopper 3u that comes into contact with the rotor in the direction of the rotation and oscillation. Cab lifting device. 2. The cab according to claim 1, wherein the abutting member 5a is configured to have a symmetrical shape and a collar-like shape in the outer circumferential direction of the piston rod 5. Lifting equipment. 3 The brim-shaped abutment member 5a has a brim-shaped axial back surface 5b having a spherical shape, and the spherical surface is
The driver's cab lifting device according to claim 2, wherein the cab lifting device has the same radius of curvature as the spherical surface formed on the surface of the rail 3e or 3q fixed to the rail.