JP2005254999A - Crawler stretching adjustment device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crawler stretching adjustment device capable of correcting stretching of the crawler to desired stretching when stretching of the crawler is increased/decreased and detecting increase/decrease of stretching of the crawler. <P>SOLUTION: A driven wheel 3 is supported on a pair of idler forks 5 and respective base ends 5a of the idler fork 5 is fixed to a support plate 6. A spring 8 and a slide body 11 are stored in an idler bracket 44 fixed to the support plate 6 and the spring 8 is guided by guide rods 9, 10. The slide body 11 is pressed to the support plate 6 side in resistant to spring force of the spring 8 by a piston rod 13, a distal end 28 of the guide rod 10b is projected from a through hole 6a formed on the support plate 6 in response to the compression state of the spring 8 and spring force accumulated in the spring 8 can be detected. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a crawler-type traveling body crawler belt tension adjusting device used in construction vehicles, civil engineering vehicles, traveling vehicles, transport vehicles, agricultural vehicles, and the like.

  Conventionally used crawler type traveling bodies include a pair of left and right track frames extending in the front-rear direction, drive wheels and driven wheels provided on both ends of each track frame, and the drive wheels and driven wheels. A crawler belt wound in between and a crawler belt tension adjusting device for adjusting the tension of the crawler belt are provided.

  A vehicle equipped with a crawler type traveling body can travel by rotating a driving wheel by driving a traveling hydraulic motor or the like and rotating a crawler belt wound between the driving wheel and a driven wheel. it can. In particular, a vehicle equipped with a crawler type traveling body is a vehicle suitable for traveling on rough terrain, wasteland, muddy land, wetland, sloping land, and the like.

  The crawler belt tension adjusting device functions so that the crawler belt wound between the driving wheel and the driven wheel has a desired tension when the vehicle including the crawler type traveling body travels. In addition, the crawler belt tension adjusting device is used when the tension of the crawler belt is abnormally increased due to foreign matter being caught between the driven wheel or the crawler belt, or a part of the crawler belt riding on an obstacle, etc. In such a case, the function of the crawler belt is avoided by moving the driven wheel toward the driving wheel.

  As the crawler belt tension adjusting device, for example, a crawler belt tension adjusting device (see Patent Document 1) that can confirm the installation position of the driven wheel, or a crawler belt that can adjust the spring force of a spring used in the crawler belt tension adjusting device. A tension adjusting device (see Patent Document 2) has been proposed.

FIG. 5 shows an enlarged cross-sectional view of main parts of the driven wheel and the crawler belt tension adjusting device in the crawler belt tension adjusting device described in Patent Document 1.
A cylindrical body 41 that accommodates a tension adjustment cylinder 51 and the like is fixed to the track frame 40 by welding together with the support plates 42 and 43 and the like inside a rectangular cylindrical track frame 40 that extends in the front-rear direction. The support plate 43 has a through hole 43A into which a nut 56 described later is inserted. The crawler belt tension adjusting device 50 includes a yoke 47, an idler wheel 48, a tension adjusting cylinder 51, a spring 58 and the like, and adjusts the tension of the crawler belt (not shown) between the idler wheel 48 and a drive wheel (not shown). can do.

  The tension adjusting cylinder 51 is provided with a spring receiving portion 52A on the outer peripheral side, and is fitted into a tube 52 having a grease chamber as a fluid storage chamber, and a base end side is slidable within the tube 52, and a distal end 53A side is a yoke. A stepped rod 53 in contact with the stepped rod 47, a grease which is located on the opposite side of the stepped rod 53 and protrudes from the tube 52 toward the support plate 43 and communicates with the grease chamber in the tube 52 at the center thereof. The grease supply / discharge rod 54 is formed with a passage.

  A stepped disk-shaped spring receiving plate 55 is inserted into the protruding end side of the grease supply / discharge rod 54, and the grease supply / discharge rod 54 is configured to be relatively displaceable with respect to the spring receiving plate 55 in the axial direction thereof. Yes. That is, in FIG. 5, the grease supply / discharge rod 54 can project through the spring receiving plate 55 in the direction of arrow B. Further, a nut 56 is screwed onto the protruding end side of the grease supply / discharge rod 54, and the grease supply / discharge rod 54 is prevented from coming off in the direction of arrow A in FIG. It is prevented.

  The side plates 44B and 44C of the idler wheel bracket 44, which is a part of the track frame 40, are formed with elongated holes 59 extending with a certain length in the sliding direction of the yoke 47. Each bearing 47B of the yoke 47 is provided with a stopper projection 60 that is screwed into the elongated hole 59. With the sliding displacement of each bearing portion 47B of the yoke 47 in the direction of arrows A and B along the guides 45 and 46 of the idler wheel bracket 44, the stopper projection 60 simultaneously moves in the elongated hole 59 as indicated by arrows A and B. The structure is displaced in the direction.

  When the vehicle is traveling, the crawler belt is deformed according to the undulations of the ground, and when a load is applied to the idler wheel 48 in the rear direction (arrow B direction), the yoke 47 that supports the idler wheel 48 is It moves in the direction indicated by arrow B along the guides 45 and 46. At this time, the tension adjusting cylinder 51 is integrated with the stepped rod 53 in contact with the yoke 47, and the spring 58 is bent and deformed via the spring receiving portion 52A, and the grease supply / discharge rod 54 is spring-received. It moves in the direction of arrow B while protruding from the plate 55.

  When the backward load (arrow B direction) acting on the idler wheel 48 decreases, the spring 58 pushes back the tension adjusting cylinder 51 in the arrow A direction by the spring force. As a result, the tension adjusting cylinder 51 is displaced in the direction indicated by the arrow A along with the yoke 47 so that the spring force of the spring 58 acts on the idler wheel 48 and gives a desired tension to the crawler belt (not shown). Can do.

  The condition of the crawler belt during traveling is determined by the initial adjustment work of the tension adjustment cylinder 51 that is performed at the time of vehicle shipment or maintenance. This initial adjustment operation is performed by injecting grease into the grease chamber of the tube 52 from the grease nipple 57 side. The rod 53 is expanded and contracted in the directions indicated by arrows A and B according to the amount of grease injected, and the initial deflection amount of the spring 58 is adjusted according to the expansion / contraction amount of the rod 53, and the initial tension (tension before traveling on the vehicle) with respect to the crawler track is adjusted. can do.

  However, if the grease is excessively injected into the tube 52 (grease chamber) of the tension adjusting cylinder 51 at the time of vehicle shipment or maintenance, the rod 53 extends greatly in the direction of arrow A from the tube 52. In the worst case, the yoke 47 may drop from the guides 45 and 46 of the idler wheel bracket 44, or the rod 53 may come out of the tube 52.

  In order to prevent this, each bearing portion 47B of the yoke 47 is provided with a stopper projection 60 projecting into the elongated hole 59 by screwing, and each bearing portion 47B of the yoke 47 is guided by the guides 45 and 46 of the idler wheel bracket 44. , The stopper projection 60 is displaced in the direction indicated by arrows A and B only within the elongated hole 59, and the amount of movement of the yoke 47 is reduced by the stopper projection 60 and the elongated hole. The structure is regulated.

  Further, in Patent Document 1, a long hole is separately formed in the side plate 44C of the idler wheel bracket 44, a scale is formed around the long hole, and an identification mark protruding from the long hole is provided with a bearing portion 47B of the yoke 47. A configuration is also disclosed in which the movement position of the yoke 47 is detected by being disposed in the position.

Patent Document 2 discloses a crawler belt tension adjusting device capable of adjusting the spring force of the spring 58 in the crawler belt tension adjusting device 50.
FIG. 6 shows a cross-sectional view of the main part configuration of the crawler belt tension adjusting device 76 described in Patent Document 2. As shown in FIG. FIG. 6 shows a cross-sectional view of the main part of a part of the yoke 74 and the crawler belt tension adjusting device 76, and the entire configuration of the driven wheel and the yoke as shown in FIG. 5 is omitted.

  The crawler belt tension adjusting device 76 includes a driven wheel (not shown), a grease cylinder 71, a spring 75, and a spring force adjusting mechanism 77. The grease cylinder 71 includes a tube 84, a piston rod 85 that defines a grease chamber in the tube 84, and a grease supply / discharge rod 73 that communicates with the grease chamber.

  The spring force adjusting mechanism 77 is positioned on the outer peripheral side of the grease supply / discharge rod 73 and is screwed to the outer peripheral side of the stopper cylinder 78 to be engaged with the stopper cylinder 78 that is in contact with the support plate 70 </ b> A of the track frame 70. A spring receiving member 79 that receives the spring force of the grease, and a rotation operation member 80 that is provided on the distal end side of the grease supply / discharge rod 73 and moves the spring receiving member 79 in the axial direction.

  The stopper cylinder 78 is formed in a long stepped cylinder, and has an external thread portion 78A on the outer peripheral surface and a large-diameter flange portion 78B that contacts the support plate 70A on the other side. A nut 81 is in contact with the nut. Further, an engagement hole 78C that engages with the engagement pin 82 is formed in the flange portion 78B.

  The spring receiving member 79 is formed in a short stepped cylindrical shape, and a female threaded portion 79A that is screwed with the male threaded portion 78A of the stopper cylinder 78 is formed on the inner peripheral side thereof. The spring receiving member 79 has a spring receiving portion 79B formed in an annular shape and rotation stop projections 79C and 79C extending from the spring receiving portion 79B in the diameter direction.

  The rotation operation member 80 is screwed into a male threaded portion 73B of a grease supply / discharge rod 73 having a grease nipple 86 at an end thereof, and a nut 81 having a pin insertion hole and a pin insertion hole of the nut 81. It is comprised from the engaging pin 82 as a coupling tool inserted and protruded toward the one side of an axial direction. The protrusion holding portion 83 formed in the track frame 70 is disposed so as to position the rotation stopping protrusion 79C and stop the rotation of the spring receiving member 79.

The spring 75 is disposed between the spring receiving portion 72A of the grease cylinder 71 and the spring receiving member 79 of the spring force adjusting mechanism 77. By moving the spring receiving member 79 in the spring force adjusting mechanism 77 in the axial direction, the spring 75 is moved. 75 spring forces can be adjusted. The movement of the spring receiving member 79 in the axial direction is caused by rotating the nut 81 to rotate the stopper cylinder 78 via the engaging pin 82 engaged with the nut 81, and as the stopper cylinder 78 rotates, the stopper cylinder 78 rotates. The spring receiving member 79 screwed into the male threaded portion 78A of the cylinder 78 can be moved by moving in the axial direction while being prevented from rotating by the protrusion holding portion 83.
JP 2000-85647 A JP 7-137672 A

  As shown in Patent Documents 1 and 2, in the conventional crawler belt tension adjusting device, the spring force of the spring is the distance between the opposed spring receiving part 52A and the spring receiving plate 55 (Patent Document 1) or the spring receiving part 13A and the spring. The spring force prescribed | regulated by the space | interval (patent document 2) with the receiving member 79 was used. In the crawler belt tension adjusting device as described in Patent Document 1, the spring receiving portion 52A is displaced toward the spring receiving plate 55 using the reaction force obtained by the stepped rod 53 pressing the yoke 47, When the interval between the spring receiving portion 52A and the spring receiving plate 55 becomes a predetermined interval, the nut 56 is brought into contact with the spring receiving plate 55 by rotating the nut 56 in a tightening direction in order to maintain the same interval. ing. Thereby, the spring force defined by the distance between the spring receiving portion 52 </ b> A and the spring receiving plate 55 can be applied to the spring 58.

  Further, in the crawler belt tension adjusting device described in Patent Document 2, by using a separately configured spring force adjusting mechanism 32, the spring force applied to the spring by adjusting the distance between the spring receiving portion 13A and the spring receiving member 79 is adjusted. Can be set. However, in the crawler belt tension adjusting device as shown in Patent Documents 1 and 2, the spring force of the spring is the distance between the opposing spring receiving part 52A and the spring receiving plate 55 (Patent Document 1) or the spring receiving part 13A and the spring receiving part. Since the spring force is defined by the distance from the member 79 (Patent Document 2), the spring force of the spring always acts as a tensile stress on the nut 56 (Patent Document 1) and the nut 81 (Patent Document 2). It has become the composition which is.

  For this reason, when the nut holding the spring force of the spring is loosened, the spring force of the spring is reduced, and it has been necessary to configure the nut so that it does not always loosen. Further, when the tension of the crawler belt wound between the driving wheel and the driven wheel decreases for some reason, the stepped rod 53 by the respective grease pressure supplied into the tension adjusting cylinder 22 or the grease cylinder 12 is used. Alternatively, even if the pressing force of the piston rod 16 is applied, even if the stepped rod 53 or the piston rod 16 moves slightly in the direction of increasing the crawler belt tension, the crawler belt tension is increased with respect to the driven wheel. It was not possible to press with a sufficient pressing force. In addition, in such a case, the spring force stored in the spring cannot be used to increase the tension of the crawler belt.

  Moreover, although the structure which confirms the installation position of a driven wheel is described in patent document 1, the structure which confirms the installation position of the driven wheel is a stage which adjusts the initial tension with respect to a crawler track as mentioned above. It is what is used. For this reason, when the tension of the crawler belt decreases, the stepped rod 53 cannot generate a sufficient pressing force as the pressing force that increases the tension of the crawler belt. Therefore, the configuration for confirming the installation position of the driven wheel has not functioned as a detection means for knowing the decrease in the crawler belt tension.

  An object of the present invention is to solve these conventional problems and to provide a crawler belt tension adjusting device in a crawler type traveling body capable of detecting a decrease in crawler belt tension even when the crawler belt tension is reduced.

The object of the present invention can be achieved by the inventions described in claims 1 to 5.
That is, in the present invention, as described in claim 1, in the crawler belt tension adjusting device for adjusting the tension of the crawler belt wound between the driving wheel and the driven wheel disposed on the track frame of the crawler type traveling body, A support plate that fixes the base ends of a pair of idler forks to which a driven wheel is attached, a sliding body that is arranged to be close to and away from the support plate, and a space between the support plate and the sliding body. A held spring, at least one guide rod provided on at least the support plate or the sliding body, for guiding the spring, and the sliding body directed toward the support plate against the spring force of the spring. And a pressing means that is restricted by the track frame to move in a direction opposite to the support plate, and is opposed to at least one guide rod tip portion. On the basis of the displacement of the guide rod tip relative to the sliding body, and forms the most important feature to become detects the spring force of the spring.

Further, in the present invention, as described in claim 2, based on the displacement from the through hole of at least one or more guide rod tips protruding from the through hole formed in the support plate or the sliding body, The main feature is to detect the spring force of the spring.
Further, in the present invention, as described in claim 3, the detection is provided on the support plate or the sliding body facing at least one or more of the guide rod tips, and is activated by contact or proximity of the guide rod tips. The main feature is that the spring force of the spring is detected based on a detection signal from the sensor.

Furthermore, in the present invention, as described in claim 4, the main feature is that the pressing means comprises a grease cylinder and a piston rod that is operated by the grease cylinder.
According to the present invention, as described in claim 5, the main feature is that the spring and the sliding body are housed in an idler bracket fixed to the support plate.

  In the present invention, as a crawler belt tension adjusting device, there is provided a structure in which a support plate to which each base end portion of a pair of idler forks attached with driven wheels is fixed is directly pressed by a spring, and a sliding body or idler that presses the other end portion of the spring. A pressing means for providing at least one guide rod having a spring guide function to the support plate to which the fork is fixed, and pressing the sliding body toward the support plate against the spring force of the spring. It has. Further, the opposite side to the support plate side of the pressing means is configured to be regulated by a track frame, and the support plate that faces at least one or more guide rod tip portions to detect the spring force of the spring. Or the information of the displacement position of the guide rod front-end | tip part with respect to a sliding body is used, It is characterized by the above-mentioned.

  This allows the driven wheel to move in the direction in which the tension of the crawler belt is adjusted by the spring force of the spring, regardless of whether the crawler belt tension wound between the drive wheel and the driven wheel increases or decreases. can do. Moreover, since the pressing force for moving the driven wheel can be applied by the spring force accumulated in the spring, a sufficient pressing force can be used as the pressing force for pressing the driven wheel.

  At this time, the spring length is changed by the compression or extension of the spring, and the change rate of the spring length and the change rate in the distance between the tip position of the guide rod that guides the spring and the support plate or the sliding body are 1: 1. It has become a correspondence relationship. In the present invention, the spring force of the spring can be detected by capturing the change in the spring length as the displacement of the guide rod tip with respect to the support plate or the sliding body.

  The guide rod can be arranged opposite to both the support plate and the sliding body, but the guide rod for detecting the change in spring length is fixed to one of the support plate and the sliding body. It is necessary to keep. Moreover, the guide rod which detects the change of the spring length is not limited to the use of only one, and a plurality of guide rods may be provided and used. In this case, the spring length of the spring can be changed in various states by appropriately combining the displacement of the guide rod tip with respect to the support plate or the sliding body by, for example, different lengths of the plurality of guide rods. Can be detected. For example, it is possible to detect a state where the spring force of the spring is within a desired range.

  The guide rod may be configured to guide the spring by loosely fitting the spring to the outer periphery of the guide rod, or the guide that regulates the outer peripheral surface side of the spring so that the spring does not bend except in the axial direction. It can also be configured as a rod.

  As a method of detecting the displacement of the guide rod tip with respect to the support plate or the sliding body, as described in claim 2, a through hole through which the tip end of the guide lot passes is formed in the support plate or the sliding body. It can be detected as a displacement of the tip end portion of the guide lot projecting from. Coloring the tip of the guide rod protruding from the through-hole, or forming a scale, etc., makes it possible to detect with visual acuity and detect the amount of protrusion more easily and reliably. it can.

  According to a third aspect of the present invention, the detection sensor is disposed on the support plate or the sliding body facing the tip end of the guide rod, and the guide rod tip contacts or approaches the detection sensor, so that the guide rod It can also be detected as a displacement of the tip. As the detection sensor, a detection sensor that can detect contact or proximity of the tip end of the guide rod, such as a piezoelectric switch, a proximity switch, or a limit switch, can be used.

  Thus, in the present invention, the spring of the spring acting on the driven wheel using the guide rod that guides the spring without using the configuration for detecting the position of the special idler wheel as in Patent Document 1. Force can be detected. For this reason, the number of parts in the configuration for detecting the spring force of the spring is small, and it can be easily assembled.

  As a pressing means that presses the sliding body against the spring force of the spring, the pressing means using the pressure of the working fluid such as a grease cylinder or a hydraulic cylinder, or the screwing of a bolt / nut or the like is used. It is possible to employ pressing means for sliding the sliding body toward the support plate, pressing means for sliding the sliding body toward the support plate using an eccentric rotation by a cam mechanism, or the like.

  When a grease cylinder or hydraulic cylinder is used as the pressing means, a pressure gauge that detects the grease pressure or hydraulic pressure is placed on the grease supply side of the cylinder or the hydraulic pressure supply side of the hydraulic cylinder. It can also comprise so that the expansion-contraction state of a spring may be detected with the pressure detected with the meter.

  Further, by controlling the grease pressure or the hydraulic pressure using a remote operation or the detection signal from the pressure gauge described above, it is possible to control the amount of expansion and contraction of the spring, constant control of the spring force of the spring, and the like. When a driving motor that drives a bolt, nut, or cam is used by a pressing means such as a bolt or nut or a pressing mechanism using a cam mechanism, the driving motor is controlled based on the detection signal from the detection sensor. It is also possible to control the spring force of the spring.

  Preferred embodiments of the present invention will be specifically described below with reference to the accompanying drawings. As the configuration of the crawler belt tension adjusting device of the present invention, in addition to the shape and arrangement described below, if the shape and arrangement can solve the problems of the present invention, those shapes and arrangement are adopted. It is something that can be done. For this reason, this invention is not limited to the Example demonstrated below, A various change is possible.

  FIG. 1 is a perspective view of a main part of a crawler belt tension adjusting device according to an embodiment of the present invention. FIG. 2 is a plan view of the crawler type traveling body provided with the crawler belt tension adjusting device, and FIG. 3 is a front view of the crawler type traveling body.

  FIG. 1 is a perspective view of a main part of a crawler belt tension adjusting device 4 in one of the pair of left and right track frames 1 in the crawler type traveling body. With respect to the other track frame, each constituent member is configured in the same manner as each constituent member shown in FIG. Therefore, in the following, the configuration of each member in one track frame 1 shown in FIGS. 1 to 3 will be described, and the description of the configuration of each member in the other track frame will be omitted. And

  As shown in FIG. 3, a drive wheel 2 is arranged on one side of the track frame 1, and is arranged so as to be able to rotate forward and backward by a drive motor 2b shown in FIG. A driven wheel 3 is disposed on the other side of the track frame 1, and the driven wheel 3 is supported by a pair of idler forks 5 on the shaft 3 a of the driven wheel 3. A crawler belt 25 is wound around the driving wheel 2 and the driven wheel 3, and the crawler belt 25 is further supported between the driving wheel 2 and the driven wheel 3 by rollers 21 a to 21 d.

  Although FIG. 3 shows an example in which the rollers 21 a to 21 d are arranged on the lower side of the track frame 1, the rollers can also be arranged on the upper portion of the track frame 1. The rollers 21a and 21b and the rollers 21c and 21d are supported by roller support plates 22a and 22b, respectively, and can be moved up and down in opposite directions by the tilting of the roller support plates 22a and 22b.

  The crawler belt 25 travels in the rotational direction of the drive wheel 2 by the rotation of the drive wheel 2. The tension of the crawler belt 25 wound between the drive wheel 2 and the driven wheel 3 can be adjusted by the crawler belt tension adjusting device 4 described below. Further, when an excessive load is applied to the crawler belt 25 or when the tension of the crawler belt 25 is likely to decrease, the crawler belt tension adjusting device 4 adjusts the tension of the crawler belt 25 to always have a constant tension force. can do.

  As shown in FIG. 1, the crawler belt tension adjusting device 4 includes a pair of idler forks 5, a support plate 6 that fixes each base end portion 5 a of the idler fork 5, and an idler bracket 44 that is fixed to the support plate 6. ing. Further, the spring 8 housed in the idler bracket 44, the sliding body 11 that is guided by the inner peripheral surface of the idler bracket 44 and slides in the idler bracket 44, and the spring 8 is guided in the idler bracket 44. Guide rods 9 and 10 are provided.

  The crawler belt tension adjusting device 4 further includes a grease cylinder 12 and a piston rod 13 that press the sliding body 11 against the spring force of the spring 8 against the support plate 6, and a track frame 1 that guides the sliding of the idler bracket 44. And a contact plate 15 for restricting movement of the grease cylinder 12 in the direction opposite to the support plate 6 between the holder 20 and the holder 20.

  One end of each of the guide rods 10a to 10c is fixed to the sliding body 11, and the springs 8a to 8c can be loosely fitted from the other end. In the support plate 6, guide rods 9a and 9b are fixed so as to face the guide rods 10a and 10c, and a through hole 6a through which the distal end portion 28 of the guide rod 10b passes is formed. The number of the springs 8 is not limited to three, but one or more can be provided.

  Alternatively, a plurality of through holes 6a may be formed so as to be opposed to the guide rods 10a and 10c, and a plurality of guide rods may be protruded from the respective through holes. The guide rod for guiding the spring 8 is not limited to the guide rod for loosely fitting the spring, but a guide rod for regulating the outer peripheral surface side of the spring so that the spring 8 does not bend in the direction other than the axial direction is used. You can also

  The distance between the guide rod 9a and the guide rod 10a and the distance between the guide rod 9b and the guide rod 10c are such that the spring 8 that accumulates a desired spring force further acts on the crawler belt 25 to increase the tension of the crawler belt 25. In order to absorb the increase, the distance allowing the support plate 6 to move toward the sliding body 11 is separated as at least the distance between the guide rods 9a, 9b and the guide rods 10a, 10c. It is desirable to keep it.

  The sliding body 11 is configured to slide using the inner peripheral surface of the idler bracket 44 fixed to the support plate 6 as a guide surface. However, the sliding body 11 is not necessarily limited to a configuration that slides within the idler bracket 44. Instead of this, it is also possible to adopt a configuration in which sliding guidance is provided by a guide member or the like formed in the holder 20.

  As shown in FIG. 2, a piston rod 13 defining a grease chamber 14 is slidably mounted in the grease cylinder 12. A connecting pipe 18 is connected to the grease chamber 14, and a grease nipple 16 is disposed at the end of the connecting pipe 18. The grease nipple 16 is supported by a grease receiver 17 fixed to the track frame 1.

  A connecting portion connected to a grease supply source (not shown) is connected to the grease nipple 16, and the grease 19 is supplied into the grease chamber 14, whereby the piston rod 13 can be slid in the left direction in FIG. By forming a communication port communicating with the drain tank or the like in the grease receiver 17, when the grease 19 is extracted from the grease chamber 14, the extracted grease can be reused. This enables the reuse of the grease that has been conventionally removed from the grease chamber and then thrown away on the ground or the like, and can be made environmentally friendly.

  By sliding the piston rod 13 leftward in FIG. 2, the piston rod 13 presses and slides the support plate 6 leftward in FIG. 2 while pressing the sliding body 11 and compressing the springs 8a to 8c. 2 moves the driven wheel 3 to the left in FIG. 2 via a pair of idler forks 5 fixed to the supporting plate 6, and the drive wheel 2 and the driven wheel 3 A desired tension can be given to the crawler belt 25 wound between the two.

  That is, the piston rod 13 is pressed by the grease 19 injected into the grease chamber 14 from the position indicated by the dotted line 13 'shown in FIG. 2 and moved to the position indicated by the solid line. As the piston rod 13 moves, the sliding plate 11 ′ located at the position indicated by the dotted line moves to the position indicated by the solid line. In this figure, the position before and after the movement of the driven wheel 3 is not shown using a dotted line, a solid line, etc. in the drawing. However, as described above, the crawler track It moves to the direction which gives tension to 25.

  The tension applied to the crawler belt 25, that is, the spring force accumulated in the springs 8a to 8c, can be determined by confirming the amount of protrusion of the guide rod 10b protruding from the through hole 6a formed in the support plate 6. it can. When it is confirmed that the desired amount of spring force has been accumulated, the grease supply from the grease supply source is stopped, and the connection portion connected to the grease supply source is removed from the grease nipple 16 so that the grease chamber 14 has a desired amount of pressure. The grease 19 that has become pressure can be filled in advance.

  Thereby, when the excessive addition is added to the crawler belt 25 and the tension | tensile_strength of the crawler belt 25 increases, the driven wheel 3 can move to the direction which compresses spring 8a-8c, and can control the increase in the tension. When the tension of the crawler belt 25 decreases for some reason, the driven wheel 3 can be moved in the direction of increasing tension by the spring force of the springs 8a to 8c, and the tension applied to the crawler belt 25 is controlled to be substantially constant. be able to.

  By forming a colored region at the distal end portion 28 of the guide rod 10b, the spring force accumulated in the springs 8a to 8c can be confirmed by confirming the colored region. Moreover, it can also be set as the structure which confirms the protrusion amount of the front-end | tip part 28 by forming a scale in the front-end | tip part 28 of the guide rod 10b. Further, a step portion is formed at the tip portion 28 of the guide rod 10b, and the large diameter side of the step portion is in contact with the through hole 6a, so that the protruding amount of the piston rod 13 is limited, and the piston rod 13 is greased. The escape from the cylinder 12 can also be prevented.

  The tip of the guide rod that protrudes from the support plate 6 is not limited to one guide rod 10b as shown in the illustrated example, but from a through-hole formed with the tip of the plurality of guide rods on the support plate. It can also protrude. In this case, it is possible to confirm the spring force of the spring in various states by using a combination of the protruding guide rod tips.

  As shown in FIG. 3, for example, when the crawler belt 25 rides on an obstacle or the like between the rollers 21 a and 21 d, the crawler belt 25 between the rollers 21 a and 21 d is placed on the crawler belt 25 due to the obstacle that rides on the crawler belt 25. Will bend upward. As a result, excessive addition is added to the crawler belt 25, and the tension of the crawler belt 25 increases. The increase in the tension in the crawler belt 25 can suppress the increase in the tension in the crawler belt 25 by moving the driven wheel 3 from the solid line position to the dotted line position, that is, by compressing the springs 8a to 8c.

  In the case shown in FIG. 3, the roller support plates 22a and 22b that respectively support the rollers 21a and 21b and the rollers 21c and 21d are tilted from the solid line state to the dotted line state 22a ′ and 22b ′. It can also help to suppress an increase in tension applied to the crawler belt 25. With this configuration, the amount of movement of the driven wheel 3 that moves to reduce the tension of the crawler belt 25 can be reduced.

  For example, when the tension of the crawler belt 25 is reduced, the roller support plates 22a and 22b are tilted in the direction opposite to the direction of the dotted line shown in FIG. 3 can be prevented in combination with the movement in the left direction in FIG. As described above, the roller support plates 22a and 22b are used together with the crawler belt tension adjusting device 4 so as to be inclined in an appropriate direction and keep the tension of the crawler belt 25 constant according to the tension condition acting on the crawler belt 25. be able to.

  In the above description, the configuration in which the sliding body 11 is pressed by the piston rod 12 has been described. However, the piston rod 13 is attached to the flange portion or the like formed in the holder 20 by contacting or fixing the grease cylinder 12 to the sliding body 11. It is also possible to adopt a configuration in which the sliding body 11 is pressed and slid by abutting. In this case, it is desirable to form a flow path through which grease passes in the piston rod 13 and to form a grease nipple at the tip of the piston rod 13.

  As the pressing means for pressing and sliding the sliding body 11, in addition to the above-described pressing means by the grease cylinder 12 and the piston rod 13, a pressing means by a screwing mechanism such as a hydraulic cylinder, a bolt and a nut, or a cam mechanism is used. A pressing means or the like can be used.

  As shown in FIG. 4, in the second embodiment according to the present invention, the tip of the guide rod abuts instead of protruding the tip of the guide rod from the through hole of the support plate in order to detect the spring force of the spring. A feature is that a detection sensor is provided at the site. About another structure, the structure similar to what was shown in Example 1 can be used, and the description is abbreviate | omitted by using the same member code | symbol as the member code | symbol used in Example 1. FIG.

  In FIG. 4, the detection sensor 27 is disposed at the portion of the support plate 6 where the guide rod 10 b fixed to the sliding body 11 abuts. When the guide rod 10b is fixed to the support plate 6, the detection sensor 27 can be disposed on the sliding body 11 side. As the detection sensor 27, various detection sensors such as a proximity switch, a limit switch, a piezoelectric switch, and a photoelectric tube that can be turned ON / OFF by being blocked or not blocked by the tip of the guide rod can be used.

  The spring force of the spring 8 can be detected using the detection signal from the detection sensor 27. Further, when the hydraulic cylinder, the above-described screwing mechanism or cam mechanism described above is driven by a drive motor using the detection signal, the drive motor can be controlled.

  The present invention can apply the technical idea of the present invention to an apparatus or the like to which the technical idea of the present invention can be applied.

It is a principal part perspective view of the crawler belt tension adjusting device concerning the embodiment of the present invention. (Example 1) It is a plane sectional view of a crawler type traveling object provided with a crawler belt tension adjusting device. (Example 1) It is a front view of a crawler type traveling body. (Example 1) It is a principal part perspective view of a crawler belt tension adjusting device. (Example 2) It is the longitudinal cross-sectional view which attached the driven wheel and the crawler belt tension adjusting device to the driven wheel bracket. (Conventional example 1) It is a cross section which shows a crawler belt tension adjusting device. (Conventional example 2)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Track frame 2 Drive wheel 3 Follower wheel 4 Crawler belt tension adjusting device 5 Idler fork 6 Support plate 7 Idler bracket 8 Spring 9 Guide rod 10 Guide rod 11 Slide body 12 Grease cylinder 13 Piston rod 14 Grease chamber 15 Contact plate 16 Grease nipple 17 Grease receptacle 18 Connection pipe 19 Grease 20 Holders 21a to 21d Rollers 22a and b Roller support plate 23 Nipple support plate 25 Crawler belt 27 Detection sensor 28 Tip 40 Track frame 44 Idle wheel bracket 47 Yoke 48 Idle wheel 50 Crawler belt tension adjusting device 51 Tension adjusting cylinder 52 Tube 52A Spring receiving portion 53 Stepped rod 54 Grease supply / discharge rod 55 Spring receiving plate 56 Nut 58 Spring 59 Long hole 60 Stopper projection 70 Track frame 71 Grease Linda 72A Spring receiving portion 73 Grease supply / discharge rod 74 Yoke 75 Spring 76 Crawler belt tension adjusting device 77 Spring force adjusting mechanism 78 Stopper cylinder 78A Male threaded portion 78B Flanged portion 79 Spring receiving member 79A Female threaded portion 79B Spring receiving portion 79C Anti-rotation Projection 80 Rotation operation member 81 Nut 82 Engagement pin 83 Projection holding part 84 Tube 85 Piston rod

Claims (5)

In the crawler belt tension adjusting device for adjusting the tension of the crawler belt wound between the driving wheel and the driven wheel arranged on the track frame of the crawler type traveling body,
A support plate that fixes each base end of a pair of idler forks to which the driven wheel is attached;
A sliding body arranged to be close to and away from the support plate;
A spring sandwiched between the support plate and the sliding body;
At least one guide rod provided on at least the support plate or the sliding body and guiding the spring;
Pressing means that presses the sliding body against the spring force of the spring toward the support plate, and the movement in the direction opposite to the support plate is restricted by the track frame;
With
A crawler belt tension adjusting device characterized by detecting a spring force of the spring based on a displacement of the tip end of the guide rod relative to the support plate or the sliding body facing at least one guide rod tip. .   The spring force of the spring is detected based on the displacement from the through hole of at least one guide rod tip protruding from the through hole formed in the support plate or the sliding body. The crawler belt tension adjusting device according to claim 1.   The spring force of the spring is based on a detection signal from a detection sensor that is disposed on the support plate or the sliding body facing the tip end of at least one guide rod and operates by contact or proximity of the tip of the guide rod. The crawler belt tension adjusting device according to claim 1, wherein the crawler belt tension adjusting device is detected.   The crawler belt tension adjusting device according to any one of claims 1 to 3, wherein the pressing means includes a grease cylinder and a piston rod that operates with the grease cylinder. 5. The crawler belt tension adjusting device according to claim 1, wherein the spring and the sliding body are housed in an idler bracket fixed to the support plate.

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